JP2010049882A - Vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle in which output deterioration of a secondary battery can be recovered using an outside power source. <P>SOLUTION: A vehicle 100 is driven with lithium ion secondary batteries 101, 102 charging with an outside power source XV and includes charge/discharge control means 20, 72, 80, S1-S30 and a deterioration detecting means M1 detecting the output deterioration of the lithium ion secondary batteries. The charge/discharge control means include outside power source charging means 72, 80, S30, deterioration evaluation means S4, S5 for evaluating the degree of output deterioration, and recovery means S17, S27 recovering the output deterioration of the secondary battery and conducting recovery charge/discharge. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle equipped with a secondary battery that can be charged by an external power source.

In recent years, electric vehicles equipped with a secondary battery as a drive source and hybrid electric vehicles equipped with an engine in addition to a secondary battery as a drive source have been put into practical use.
As a secondary battery used in such a vehicle, for example, Patent Document 1 discloses a lithium ion secondary battery in which LiPF ₆ is used as a non-aqueous electrolyte and a lithium salt concentration is 0.4 to 0.8 mol / L. Are listed. Patent Document 2 describes a lithium ion secondary battery in which a low crystalline carbon material is used for the negative electrode and the concentration of the lithium salt in the non-aqueous electrolyte is 0.7 to 0.9 mol / L. .

JP 2000-021441 A JP 2002-231316 A

However, in the lithium ion secondary batteries described in Patent Document 1 and Patent Document 2, when the discharge or charging at a high rate is repeated, an output deterioration phenomenon in which the internal resistance of the secondary battery gradually increases has been found.
It was also discovered that the concentration of lithium ions in the retained electrolyte held between the positive electrode plate and the negative electrode plate of the power generation element fluctuates with the output deterioration phenomenon of the secondary battery. Furthermore, it has been found that the internal resistance of the secondary battery is increased even when the concentration of lithium ions in the retained electrolyte changes higher or lower than the initial value.
Further, the present inventors have found that the internal resistance of the secondary battery can be gradually reduced by appropriately adjusting the charging / discharging conditions for the lithium ion secondary battery having an increased internal resistance. . Specifically, for such a secondary battery, if charging and discharging are repeated with a predetermined balance between the current value during charging and the current value during discharging, the internal resistance gradually decreases and the output deterioration is recovered. be able to. It was confirmed that when such charge and discharge were repeated, the concentration of lithium ions in the retained electrolyte in the secondary battery also returned to the initial concentration.

  By utilizing this knowledge, by controlling the charging / discharging of the lithium ion secondary battery, the increase in the internal resistance of the secondary battery is suppressed, and further, the internal resistance is reduced to reduce the output of the secondary battery. A battery system that can recover the battery, a vehicle equipped with the battery system, and a battery-equipped device are conceivable.

As a vehicle equipped with such a battery system, a vehicle equipped with an engine and capable of being charged and discharged by itself, for example, a hybrid electric vehicle is conceivable. In such a hybrid electric vehicle, for example, when the output of the secondary battery is recovered using the battery system, the vehicle is running.
However, in order to recover the deterioration of the secondary battery, when trying to adjust the charging current and the discharging current during traveling, for example, when the vehicle wants to take out the battery output necessary for traveling from the secondary battery, There is a possibility that the secondary battery cannot discharge a current value having a magnitude corresponding to the battery output. For this reason, there is a possibility that the required running performance cannot be sufficiently satisfied during the period of deterioration recovery.

  The present invention has been made in view of such a problem, and an object of the present invention is to provide a vehicle that can recover output deterioration of a secondary battery using an external power source.

  And the solution means is a vehicle equipped with a secondary battery which can be charged by an external power source installed outside itself, and is driven by the secondary battery, wherein the secondary battery is a lithium ion secondary battery Charge / discharge control means for controlling charge / discharge of the lithium ion secondary battery and deterioration detection means for detecting output deterioration of the lithium ion secondary battery, wherein the charge / discharge control means is the external External power source charging means for charging the lithium ion secondary battery with a power source, deterioration evaluation means for evaluating the degree of output deterioration of the lithium ion secondary battery detected by the deterioration detection means, and the deterioration evaluation means And a recovery means for performing recovery charge / discharge for recovering the output deterioration of the lithium ion secondary battery when the output deterioration is evaluated to be a predetermined deterioration state. It is.

  The vehicle of the present invention includes a secondary battery that can be charged by an external power source, and includes charge / discharge control means including external power source charging means, deterioration evaluation means, and recovery means in addition to the deterioration detection means. Accordingly, the vehicle can be easily recovered from the output deterioration of the secondary battery in a predetermined deterioration state by performing recovery charge / discharge using an external power source.

  As the vehicle, for example, in addition to a plug-in hybrid electric vehicle and a plug-in electric vehicle that are charged with a secondary battery by inserting a plug into an external power outlet installed outside the vehicle, the vehicle is installed outside. An electric vehicle or the like that is charged using a charger (external power supply device).

Further, the deterioration evaluation means can evaluate the degree of output deterioration of the secondary battery based on the detection result of the deterioration detection means. For example, when the concentration of lithium ions in the excess electrolyte stored outside the power generation element in the battery case of the secondary battery (hereinafter also referred to as excess electrolyte concentration) is detected, this concentration is equal to or higher than the first predetermined value. If it is, it is evaluated that it is deteriorated, or it is evaluated that it is deteriorated when it is equal to or less than the second predetermined value.
Furthermore, the evaluation by the degradation evaluation means may be started by an instruction input by the driver or input by the operator at the time of inspection at a dealer or the like, for example. The evaluation may be performed every time the secondary battery is charged by the external power source. For example, the evaluation may be performed intermittently according to the number of times of charging by the external power source counted by the counter, or the previous evaluation may be performed by the timer. Evaluation may be performed in charging at a timing when a predetermined time elapses.

  The deterioration detection means may be any means that can detect the output deterioration of the secondary battery. Specifically, the deterioration of the output of the secondary battery based on the change in the excess electrolyte concentration (the increase in the excess electrolyte concentration). And a means for detecting changes in the concentration of lithium ions in the retained electrolyte between the electrodes of the power generation element (hereinafter also referred to as retained electrolyte concentration), changes in the internal resistance of the secondary battery, and the like.

The recovery means applies charge / discharge of a pattern that can recover the degree of deterioration of the secondary battery to the secondary battery.
For example, when the excess electrolyte concentration is high (for this reason, the internal resistance is high), the first charging is performed for a short time with the first charging current (for example, the maximum charging current that can be charged by an external power source). There is one that repeatedly discharges for a long time with a current relatively smaller than the current (for example, about 1/5 of the maximum charging current). Thereby, the density | concentration of an excess electrolyte solution can be reduced (internal resistance is reduced), and a secondary battery can be recovered.
On the other hand, when the surplus electrolyte concentration is low (for this reason, the internal resistance is high), the second charging current (for example, a current that is about 1/5 of the maximum charging current) is charged for a long time. There is one that repeatedly discharges for a short time with a current relatively larger than the charging current (for example, about the maximum charging current). As a result, the secondary battery can be recovered by increasing the excess electrolyte concentration (decreasing the internal resistance).

  In addition, in the charge / discharge of the pattern that can recover the degree of deterioration of the secondary battery, the amount of electricity to be charged may be different from the amount of electricity to be discharged, but it is preferable that they be the same. If the amount of electricity to be charged is the same as the amount of electricity to be discharged, for example, when a pair of charge / discharge combinations of one charge and one discharge is performed, before this pair of charge / discharge Later, the state of charge will be the same. For this reason, even if charge / discharge of a plurality of pairs is repeated on the secondary battery, the state of charge of the secondary battery at the end of charging (or discharging) can be made the same every time. Therefore, for example, while charging / discharging by the recovery means is repeated, there is no possibility that the charging state of the secondary battery gradually shifts to the overcharge side or the overdischarge side, and it is safe to repeat the charge / discharge in the recovery means. It can be carried out.

  Furthermore, in the above-described vehicle, the charge / discharge control means performs evaluation by the deterioration evaluation means before completion of charging by the external power supply charging means, and the deterioration evaluation means is in the predetermined deterioration state. If the vehicle is evaluated, the vehicle may be recovered by the recovery means.

  The vehicle of the present invention evaluates output deterioration in the secondary battery before completion of charging by the external power source, and also performs recovery by recovery means depending on the case. For this reason, when the output deterioration of the secondary battery is in a predetermined deterioration state, the recovery charge / discharge can be performed and easily recovered. In addition, the charging of the secondary battery can be completed in a state where the evaluation of the output deterioration of the secondary battery and, in some cases, the recovery are reliably completed.

  Furthermore, in any one of the above-described vehicles, the charge / discharge control unit may perform charge / discharge of the lithium ion secondary battery when the deterioration evaluation unit evaluates the predetermined deterioration state. It is preferable that the charging unit includes a charging state adjusting unit that adjusts the charging state to a predetermined charging state, and the recovery unit is a vehicle that performs the recovery charging / discharging after the adjustment to the predetermined charging state.

The present inventors have found that the degree of recovery varies depending on the state of charge (SOC) of the secondary battery when performing recovery charge / discharge on the secondary battery.
Therefore, in the vehicle of the present invention, when the battery is in a predetermined deterioration state, recovery charge / discharge is performed in advance after the secondary battery is brought into a predetermined charge state (SOC) by the charge state adjusting means. As a result, the secondary battery can always be recovered in the same manner.

In addition, as a predetermined charging state, it is preferable to set it as the charging state of the secondary battery suitable for performing recovery charge / discharge. For example, the cathode active material is composed of lithium nickelate (LiNiO ₂ ) 87 wt%, conductive agent acetylene black 10 wt%, binder polytetrafluoroethylene (PTFE) 1 wt%, and carboxymethyl cellulose (CMC) 2 wt%. In the case of a lithium ion secondary battery having a positive electrode active material layer and a negative electrode active material layer composed of 98 wt% of the negative electrode active material graphite and 2 wt% of the binder, the state of charge (SOC) is 55%. It is preferable to be -65% (for example, 60%).

  Furthermore, in any one of the vehicles described above, the charge / discharge control unit detects the deterioration of the lithium ion secondary battery detected by the deterioration detection unit after the recovery charge / discharge by the recovery unit is completed. It includes a recovery evaluation unit that evaluates the degree of output deterioration, and the recovery unit may be a vehicle that performs the recovery charge / discharge again when it is evaluated by the recovery evaluation unit that the predetermined recovery state has not been reached. .

  In the vehicle of the present invention, the charge / discharge control means includes the recovery evaluation means, and the recovery charge / discharge is performed again when the predetermined recovery state has not been reached, so that the output deterioration of the secondary battery can be reliably recovered. .

  The predetermined recovery state in the recovery evaluation means is, for example, the range of excess electrolyte concentration, the range of retained electrolyte concentration, the range of the magnitude of change of these concentrations before and after recovery, or the size of internal resistance. It can be specified in the range.

  Furthermore, in any one of the vehicles described above, the recovery means includes a short-time charge with a first charge current to the lithium ion secondary battery and a first discharge that is relatively smaller than the first charge current. It is preferable that the vehicle has a first recovery means for performing a first recovery charge / discharge that is performed at least once for charging / discharging due to a long-term discharge with current.

In the vehicle of the present invention, the first recovery charge / discharge is performed by the first recovery means. This first recovery charge / discharge is effective for output deterioration that is likely to occur when the secondary battery is discharged at a high (high rate) discharge current (prone to occur when the vehicle is suddenly accelerated or suddenly started). It is. In other words, this is effective for deterioration (output deterioration) in which the surplus electrolyte concentration of the secondary battery increases, the retained electrolyte concentration decreases, and the internal resistance of the secondary battery increases. When the first recovery charge / discharge is used, the secondary battery whose output has deteriorated as described above can be appropriately recovered.
The recovery means may include only the first recovery means described above or other means (for example, the second recovery means described below).

Furthermore, in the vehicle described above, the first recovery means performs charging / discharging by the same first electric quantity during short-time charging with the first charging current and long-time discharging with the first discharging current, It is preferable to use a vehicle that repeats this multiple times.
In this vehicle, the same first electric quantity is charged / discharged by a pair of charging / discharging of the short-time charging with the first charging current and the long-time discharging with the first discharging current, and this is repeated a plurality of times (multiple pairs). . For this reason, even if it repeats this pair of charging / discharging several times with respect to a secondary battery, the charge condition of the secondary battery at the time of completion | finish of each time (a pair) charging / discharging can be made the same. Therefore, for example, while repeating charge and discharge in the first recovery means, there is no risk that the state of charge of the secondary battery gradually shifts to the overcharge side or the overdischarge side, and charge and discharge for recovery is performed. Can be repeated multiple times safely and reliably.

  Alternatively, in any one of the vehicles described above, the recovery means may charge the lithium ion secondary battery for a long time with a second charging current and a second discharge that is relatively larger than the second charging current. It is preferable that the vehicle has a second recovery means for performing a second recovery charge / discharge that is performed at least once for the charge / discharge by the short-time discharge with the electric current.

In the vehicle of the present invention, the second recovery charge / discharge is performed by the second recovery means. This second recovery charge / discharge is effective for output degradation that is likely to occur when the secondary battery is repeatedly charged (charged by regenerative operation of the vehicle) in which the secondary battery is charged with a high (high rate) charge current. That is, it is effective for the deterioration of the output of the secondary battery in which the surplus electrolyte concentration decreases and the retained electrolyte concentration increases. When the second recovery charge / discharge is used, the secondary battery whose output has deteriorated as described above can be appropriately recovered.
The recovery means may include only the second recovery means described above or other means.

Further, in the vehicle described above, the second recovery means performs charging / discharging by the same second amount of electricity during long-time charging with the second charging current and short-time discharging with the second discharging current, It is preferable to use a vehicle that repeats this multiple times.
In this vehicle, the same second electric quantity is charged / discharged by a pair of charging / discharging of the long-time charging with the second charging current and the short-time discharging with the second discharging current, and this is repeated a plurality of times (multiple pairs). . For this reason, even if it repeats this pair of charging / discharging several times with respect to a secondary battery, the charge condition of the secondary battery at the time of completion | finish of each time (a pair) charging / discharging can be made the same. Therefore, for example, while repeating the charging / discharging in the second recovery means, there is no possibility that the charging state of the secondary battery gradually shifts to the overcharge side or the overdischarge side, and charge / discharge for recovery is performed. Can be repeated multiple times safely and reliably.

  Alternatively, in any one of the above-described vehicles, the recovery means may charge the lithium ion secondary battery for a short time with a first charging current and a first discharge relatively smaller than the first charging current. A first recovery means for performing a first recovery charge / discharge for at least one charge / discharge by a long-time discharge with a current; a long-time charge to the lithium ion secondary battery with a second charge current; A second recovery means for performing a second recovery charge / discharge at least once for charge / discharge by a short-time discharge with a second discharge current relatively larger than two charge currents, the charge / discharge control means Is preferably a vehicle including a selection means for selecting which of the first recovery means and the second recovery means to execute based on the evaluation of the deterioration state by the deterioration evaluation means.

  In the vehicle of the present invention, since the recovery means includes the first recovery means and the second recovery means, the secondary battery can be appropriately recovered in accordance with two types of deterioration modes that can occur in the secondary battery. it can.

Furthermore, in the vehicle described above, the first recovery means performs charging / discharging by the same first electric quantity during short-time charging with the first charging current and long-time discharging with the first discharging current, This is repeated a plurality of times, and the second recovery means performs charging / discharging by the same second amount of electricity during long-time charging with the second charging current and short-time discharging with the second discharging current. The vehicle is preferably repeated twice.
In this vehicle, the same first electric quantity is charged / discharged by a pair of charging / discharging of the short-time charging with the first charging current and the long-time discharging with the first discharging current, and this is repeated a plurality of times (multiple pairs). . For this reason, even if it repeats this pair of charging / discharging several times with respect to a secondary battery, the charge condition of the secondary battery at the time of completion | finish of each time (a pair) charging / discharging can be made the same.
Moreover, the same 2nd electric quantity is charged / discharged by a pair of charging / discharging with long-time charge with a 2nd charging current, and short-time discharge with a 2nd discharge current, and this is repeated several times (multiple pairs). For this reason, even if it repeats this pair of charging / discharging several times with respect to a secondary battery, the charge condition of the secondary battery at the time of completion | finish of each time (a pair) charging / discharging can be made the same.
Therefore, for example, while repeating the charge / discharge in the first recovery means or the second recovery means, there is no possibility that the charging state of the secondary battery gradually shifts to the overcharge side or the overdischarge side, Charging / discharging for recovery can be repeated multiple times safely and reliably.

  Furthermore, in any one of the vehicles described above, the deterioration detection unit detects excess lithium ion concentration in an excess electrolyte stored outside the power generation element in the battery case of the lithium ion secondary battery. The vehicle may be liquid concentration detection means.

  In the vehicle of the present invention, since the deterioration detecting means is the surplus electrolyte concentration detecting means, it is possible to determine the output deterioration of the secondary battery from the level of the surplus electrolyte concentration. Therefore, it is possible to easily judge the output deterioration.

(Embodiment 1)
Next, Embodiment 1 of the present invention will be described with reference to the drawings.
First, the vehicle 100 according to the first embodiment will be described. FIG. 1 shows a perspective view of the vehicle 100.
In addition to a plurality of lithium ion secondary batteries 101 and 102 (hereinafter also referred to as batteries 101 and 102) that form the assembled battery 10, the vehicle 100 includes a plug-in hybrid vehicle control device (hereinafter also referred to as a PHV control device). 20, a plug-in hybrid electric vehicle having a front motor 30, a rear motor 40, an engine 50, a cable 60, an inverter 71, a converter 72, a vehicle body 90, and a cable 80 with a plug. That is, the vehicle 100 can be driven using the front motor 30 and the rear motor 40 in the same manner as an electric vehicle during the start-up of the vehicle, and the engine 50, the front motor can be driven in the same manner as a hybrid electric vehicle. 30 and the rear motor 40 can be used in combination. On the other hand, after the start of the vehicle is completed, the plug 80P of the plug-attached cable 80 is inserted into the external power source XV installed outside the vehicle 100 in the same manner as the electric vehicle, and a plurality of batteries in the assembled battery 10 are inserted. 101 and 102 can be charged.

  Among these, the PHV control device 20 includes a microcomputer that has a CPU, a ROM, and a RAM (not shown) and operates according to a predetermined program. The PHV control device 20 can communicate with a front motor 30, a rear motor 40, an engine 50, an inverter 71, a converter 72, and a battery monitoring device 12 (described later) connected by a communication cable 12B. Various controls are performed according to the situation. For example, the combination of the driving force of the engine 50 and the driving force of the motors 30 and 40 according to the traveling state of the vehicle 100 is controlled, or the assembled battery 10 (batteries 101 and 102 is supplied from the external power source XV through the cable 80 with a plug. ) Is charged when charging.

  As shown in FIG. 2, the assembled battery 10 includes a battery unit 11 in which a plurality of batteries 101 and 102 are arranged in an assembled battery case 11 </ b> A, and a battery monitoring device 12. Among these, the battery monitoring device 12 acquires data on the state (battery temperature and voltage) of the plurality of batteries 101 and 102 of the battery unit 11 using a thermistor and a sensing wire (not shown).

The battery unit 11 includes a wound battery 101 including a power generation element 120 and an electrolytic solution 130 as well as a surplus electrolyte concentration detecting means M1 described later, and a surplus electrolyte concentration in a rectangular box-shaped battery case 110. Two types of batteries, which are different from the battery 101 only in that the detection means M1 is not provided, are included. The plurality of batteries 101 and 102 are connected in series with each other by bolt fastening with the bus bar 190.
Among these, the battery 101 provided with the excess electrolyte concentration detection means M1 will be described with reference to FIGS.

  The battery case 110 of the battery 101 includes a battery case body 111 and a sealing lid 112 both made of stainless steel (see FIG. 3). Among these, the battery case main body 111 has a bottomed rectangular box shape, and an insulating film made of resin (not shown) is pasted on the entire inner surface.

The sealing lid 112 has a rectangular plate shape, closes the opening 111A of the battery case body 111, and is welded to the battery case body 111 (see FIGS. 3 and 4). In the sealing lid 112, the positive electrode current collecting member 171 and the negative electrode current collecting member 172 connected to the power generation element 120 have the positive electrode terminal portion 171A and the negative electrode terminal portion 172A located at the tips thereof from the upper surface 112a to the battery case. Projecting toward the outside of 110. A resin insulating member 175 is interposed between the positive terminal portion 171A and the negative terminal portion 172A and the sealing lid 112 to insulate each other.
Further, a first conducting wire 142 of the first measuring electrode 140 and a second conducting wire 152 of the second measuring electrode 150, which will be described later, penetrate the sealing lid 112 and protrude from the upper surface 112a (see FIGS. 3 and 4). . Further, a rectangular plate-shaped safety valve 177 is also sealed on the sealing lid 112.

The power generation element 120 is formed by winding a belt-like positive electrode plate 121 and a negative electrode plate 122 into a flat shape via a belt-like separator 123 made of polyethylene (see FIG. 5). The positive electrode plate 121 and the negative electrode plate 122 of the power generation element 120 are joined to a plate-like positive electrode current collector 171 or a negative electrode current collector 172 bent in a crank shape, respectively.
Note that approximately half (upper side in FIG. 5) of the negative electrode lead portion 122 f made of copper foil is in close contact with and welded to the negative electrode current collector 172. Although not shown, the positive electrode lead portion 121f of the positive electrode plate 121 is also welded to the positive electrode current collecting member 171 in the same manner as the negative electrode side.

The positive electrode plate 121 is formed by supporting a positive electrode active material layer (not shown) on both surfaces of the strip-shaped aluminum foil, leaving a positive electrode lead portion 121f along one long side. This positive electrode active material layer includes lithium nickel oxide (LiNiO ₂ ) as a positive electrode active material, acetylene black as a conductive agent, and polytetrafluoroethylene (PTFE) and carboxymethyl cellulose (CMC) as a binder. The mass ratio of the positive electrode active material layer is 87 wt% for LiNiO ₂ , 10 wt% for acetylene black, 1 wt% for PTFE, and 2 wt% for CMC.
Moreover, the negative electrode plate 122 carries the negative electrode active material layer which is not shown in figure on both surfaces, leaving the negative electrode lead part 122f along one long side among strip | belt-shaped copper foil. This negative electrode active material layer contains graphite and a binder.

In addition, the electrolyte solution 130 is a mixed organic solvent in which ethylene carbonate (EC), ethyl methyl carbonate (EMC), and dimethyl carbonate (DMC) are adjusted to a volume ratio of EC: EMC: DMC = 3: 4: 3. This is an organic electrolytic solution in which LiPF ₆ is added as a solute and the concentration of lithium ions LH is 1 mol / L.
In the first embodiment, the electrolytic solution 130 is classified as follows according to the difference in the portion to be held. That is, in the power generation element 120 described above, the electrolytic solution retained between the positive electrode plate 121 and the negative electrode plate 122 is referred to as a retained electrolytic solution 130H. In addition, as shown in FIG. 4, by injecting more electrolytic solution into the battery case 110 than being held in the power generation element 120, the power generation element 120 and the power generation element 120 can be circulated with each other. Among the battery case 110, the electrolyte stored in the lower part 110B inside the battery case 110 is referred to as a surplus electrolyte 130S.

  Next, the surplus electrolyte concentration detection means M1 will be described. The excess electrolyte concentration detection means M1 is immersed in the first measurement electrode 140, the reference electrolyte 160, the cylindrical container 161 that accommodates the reference electrolyte 160, and the reference electrolyte 160 that are immersed in the excess electrolyte 130S. The second measurement electrode 150 and the filter 180 that isolates the excess electrolyte solution 130S and the reference electrolyte solution 160 are provided (see FIG. 4).

Among these, the 1st measurement electrode 140 has the 1st electrode main-body part 141 holding the 1st metal plate 141L which consists of metallic lithium, and the 1st conducting wire 142. FIG. The first metal plate 141 </ b> L is held (supported) on both surfaces of a rectangular mesh-shaped support body 142 </ b> A made of nickel, which is disposed on the distal end side of the first conductive wire 142. Among these, the 1st conducting wire 142 covers the circumference | surroundings of the nickel wire 142X electrically connected with the 1st electrode main-body part 141 with insulating resin.
Similarly to the first measurement electrode 140 described above, the second measurement electrode 150 includes a second electrode main body 151 that holds a second metal plate 151 </ b> L made of metallic lithium, and a second conductor 142. The second metal plate 151 </ b> L is held (supported) on both surfaces of a rectangular mesh-shaped carrier 152 </ b> A made of nickel, which is disposed on the distal end side of the second conductive wire 152. Among these, the 2nd conducting wire 152 covers the circumference | surroundings of the nickel wire 152X with insulating resin like the 1st measurement electrode 140. FIG.

The 1st electrode main-body part 141 of the 1st measurement electrode 140 is immersed in the above-mentioned excess electrolyte solution 130S. On the other hand, in the second measurement electrode 150, a part of the second electrode main body 151 and the second conducting wire 152 is disposed in a glass cylindrical container 161. In this cylindrical container 161, a reference electrolytic solution 160 having the same composition as the above-described electrolytic solution 130, that is, ethylene carbonate (EC), ethyl methyl carbonate (EMC), and dimethyl carbonate (DMC) in a volume ratio EC: Electrolysis in which LiPF ₆ was added as a solute to a mixed organic solvent adjusted to EMC: DMC = 3: 4: 3, and the concentration of lithium ion LH (hereinafter also simply referred to as concentration) BC was adjusted to a reference concentration of 1 mol / L. Liquid is enclosed. Therefore, the second electrode main body 151 of the second measurement electrode 150 is immersed in the reference electrolyte 160 in the cylindrical container 161.

  As shown in FIG. 4, the bottom 161B of the cylindrical container 161 described above is immersed in the excess electrolyte solution 130S. Incidentally, a filter 180 made of a porous glass plate is provided on the bottom 161B of the cylindrical container 161. The filter 180 prevents ion migration due to a concentration difference between the surplus electrolyte 130S and the reference electrolyte 160, and the surplus electrolyte 130S and the reference electrolyte by the first measurement electrode 140 and the second measurement electrode 150. Allows measurement of potential between 160.

  In addition, the 1st conducting wire 142 of the 1st measurement electrode 140 is being fixed to the inner side of the battery case main body 111 via the two fixing members 142Z which consist of resin. Thereby, since the 1st electrode main-body part 141 of the 1st measurement electrode 140 escapes the contact with the electric power generation element 120, for example, generation | occurrence | production of the short circuit in the battery 101 can be suppressed. Similarly, the second conducting wire 152 of the second measuring electrode 150 is fixed. On the other hand, the cylindrical container 161 is also bonded to the inside of the battery case main body 111.

  The surplus electrolyte concentration detecting means M1 constitutes a concentration cell with the surplus electrolyte 130S and the reference electrolyte 160. The first electrode main body 141 of the first measurement electrode 140 and the second measurement are described below. By measuring the electromotive force VP between the electrode 150 and the second electrode body 151, the lithium ion concentration SC of the surplus electrolyte 130S can be detected (see FIG. 6). Thereby, the magnitude | size and height of internal resistance BR of the battery 101 can be estimated.

By the way, when the inventors repeatedly charge and discharge the batteries 101 and 102, which are lithium ion secondary batteries, when the discharge current larger than the charge current, particularly when the high-rate discharge current is passed, It has been found that the internal resistance BR is likely to increase. However, it has been found that even when the battery is deteriorated in this way, the internal resistance BR of the batteries 101 and 102 returns (decreases) when charging and discharging are repeated with the discharge current relatively smaller than the charging current.
Further, conversely, even when a charging current larger than the discharging current, particularly a high rate charging current is passed, it has been detected that the internal resistance BR of the batteries 101 and 102 increases. However, even when such deterioration occurs, it has also been found that the internal resistance BR of the batteries 101 and 102 returns (decreases) when charging and discharging are repeated with the charging current relatively smaller than the discharging current.

Furthermore, the inventors have obtained knowledge about the correlation with the lithium ion concentration SC of the excess electrolyte 130S when the battery 101 has various internal resistances BR due to high-rate charging or discharging.
Specifically, as shown in FIG. 7, when the lithium ion concentration SC of the surplus electrolyte 130S is higher or lower than 1.0 mol / L, the internal resistance BR of the battery 101 is increased. It can be seen that shows a tendency to increase. More specifically, the battery 101 has a positive correlation that, for example, in the range where the lithium ion concentration SC of the surplus electrolyte 130S is 1.2 mol / L or higher, the higher the lithium ion concentration SC, the higher the internal resistance BR. I understand that. On the other hand, in the range of 0.8 to 1.1 mol / L, it can be seen that the lithium ion concentration SC and the internal resistance BR have little correlation, and the internal resistance BR maintains a low value. On the other hand, in the range of less than 0.8 mol / L, it can be seen that there is a negative correlation that the internal resistance BR is higher as the lithium ion concentration SC is lower.

  Furthermore, the inventors charge and discharge the batteries 101 and 102 whose internal resistance BR has increased due to deterioration, and in reducing and recovering the internal resistance, depending on the state of charge (SOC) of the batteries 101 and 102, We found that the degree of recovery was different. That is, in the batteries 101 and 102, when charging / discharging for recovery is performed in a state where the charged state is 55 to 65% of the full charge (SOC 55 to 65%), the output deterioration is recovered. It turned out that it was easy to make it.

  Based on the above knowledge, the vehicle 100 according to the first embodiment detects the deterioration of the batteries 101 and 102 and recovers the deterioration as follows (see FIG. 8).

First, when the start of the vehicle 100 is finished (KEY OFF) (step S1), the CPU (not shown) of the PHV control device 20 performs intermittent start using a timer and an internal battery (not shown), It is detected whether or not a voltage is applied through the plug-attached cable 80 (step S2).
Here, if NO, ie, no voltage is applied to the converter 72 (the plugged cable 80 is not connected to the external power source XV), step S2 is repeated. On the other hand, if YES, that is, if a voltage is applied to the converter 72, the process proceeds to step S3, and the first electrode main body 141 and the second electrode main body 151 are detected using the surplus electrolyte concentration detecting means M1 of the battery 101. The electromotive force VP generated between the two is measured.

  Here, in FIG. 9, the PHV control device 20, the battery monitoring device 12, and the battery 101 are extracted and shown. Among these, the battery monitoring device 12 has a battery monitoring device main body 12A including an electromotive force acquisition circuit 12A1, and communicates with the PHV control device 20 via a communication cable 12B. Among these, the electromotive force acquisition circuit 12A1 is connected to the surplus electrolyte concentration detection means M1 of the battery 101, and detects the electromotive force VP between the first electrode main body 141 and the second electrode main body 151. Then, the detected electromotive force VP is transmitted to the PHV control device 20 through the communication cable 12B.

In step S4, the PHV controller 20 determines whether or not the electromotive force VP is greater than the first electromotive force threshold VP1.
In the first embodiment, for example, VP1 = 13 mV (see FIG. 6). This value (13 mV) corresponds to the case where the lithium ion concentration SC of the excess electrolytic solution 130S is the first concentration threshold SC1 (= 1.2 mol / L). Further, according to FIG. 7, this value corresponds to the case where the internal resistance BR of the battery 101 is the first resistance threshold value BR1 (= 4.7 mΩ).
Therefore, by determining whether or not the electromotive force VP is larger than the first electromotive force threshold value VP1, it can be estimated whether or not the lithium ion concentration SC is larger than the first concentration threshold value SC1 (see FIG. 6). Furthermore, this estimation makes it possible to estimate whether or not the internal resistance BR of the battery 101 is greater than the first resistance threshold value BR1 (see FIG. 7).
If YES, that is, if the electromotive force VP is larger than the first electromotive force threshold VP1 (VP> VP1), the process proceeds to step S10.

On the other hand, if NO, that is, if the electromotive force VP is equal to or less than the first electromotive force threshold VP1 (VP ≦ VP1), the process proceeds to step S5, and the PHV control device 20 has a third electromotive force threshold smaller than the first electromotive force threshold VP1. It is determined whether the electromotive force VP is smaller than VP3.
In the first embodiment, for example, VP3 = −12 mV (see FIG. 6). This value (−12 mV) corresponds to the case where the lithium ion concentration SC of the excess electrolytic solution 130S is the third concentration threshold SC3 (= 0.8 mol / L). Further, according to FIG. 7, this value corresponds to the case where the internal resistance BR of the battery 101 is 4.0 mΩ (= third resistance threshold value BR3).
Therefore, by determining whether or not the electromotive force VP is smaller than the third electromotive force threshold value VP3, it is possible to estimate whether or not the concentration SC is smaller than the third concentration threshold value SC3 (see FIG. 6). Furthermore, this estimation makes it possible to estimate whether or not the internal resistance BR of the battery 101 is smaller than the third resistance threshold BR3 (see FIG. 7).

If YES in step S5, that is, if the electromotive force VP is smaller than the third electromotive force threshold VP3 (VP <VP3), the process proceeds to step S20, and the total voltage VA of the assembled battery 10 is measured.
On the other hand, when NO, that is, when the electromotive force VP is equal to or greater than the third electromotive force threshold VP3 (VP ≧ VP3), it is not necessary to recover the deterioration (VP3 ≦ VP ≦ VP1). Charging is started and the battery pack 10 is fully charged. Specifically, constant current charging is performed with a charging current of 5A (1C) using the converter 72, the cable with plug 80, and the external power source XV, and the assembled battery 10 is fully charged (SOC 100%).

  In step S <b> 10, the total voltage VA (total voltage of each battery 101 and battery 102) of the assembled battery 10 (battery unit 11) composed of a plurality of batteries 101 and batteries 102 is measured, and the batteries 101 and 102 forming the assembled battery 10 are measured. The state of charge (SOC) is estimated. As a characteristic of the lithium ion secondary battery, it is known that the SOC is uniquely determined from the battery voltage. For example, when the batteries 101 and 102 according to the first embodiment are SOC 60%, the voltage is 3. Therefore, the total voltage VA of the battery pack 10 when the SOC is 60% is (3.726 × 56) V.

  In step S11, it is determined whether or not the total voltage VA is larger than (3.726 × 56) V. Here, if YES, that is, if the SOC of the assembled battery 10 is larger than SOC 60%, the process proceeds to step S13 and the assembled battery 10 is discharged.

  Specifically, in step S13, constant current discharge is performed from the assembled battery 10 with a discharge current of 5A (1C), and the assembled battery 10 (batteries 101 and 102) is lowered to SOC 60%. In the vehicle 100 of the first embodiment, for example, the assembled battery 10 is discharged by operating a cooling fan (not shown) that cools the assembled battery 10.

  In step S14, the discharging in step S13 is continued until the total voltage VA of the assembled battery 10 reaches (3.726 × 56) V. When the total voltage VA of the assembled battery 10 becomes (3.726 × 56) V, the process proceeds to step S17, and charging / discharging for recovering deterioration described later is performed.

On the other hand, if NO in step S11, that is, if the total voltage VA of the assembled battery 10 is (3.726 × 56) V or less (VA ≦ (3.726 × 56) V), the process proceeds to step S12. It is determined whether or not the total voltage VA of the assembled battery 10 is equal to (3.726 × 56) V. If YES, that is, if the total voltage VA of the assembled battery 10 is equal to (3.726 × 56) V, the process proceeds to step S17.
On the other hand, if NO in step S12, that is, if the total voltage VA of the assembled battery 10 is smaller than (3.726 × 56) V (VA <(3.726 × 56) V), the process proceeds to step S15.

  In step S15, since the SOC of the battery pack 10 (batteries 101 and 102) is lower than SOC 60%, the battery pack 10 is charged from the external power source XV through the plug-attached cable 80 and the converter 72. Specifically, constant current charging is performed with a charging current of 5A (1C), and the SOC of the battery pack 10 (batteries 101 and 102) is set to SOC 60%.

  Therefore, the charging in step S15 is continued until it is determined in step S16 whether the total voltage VA of the assembled battery 10 is equal to (3.726 × 56) V. When the total voltage VA of the assembled battery 10 reaches (3.726 × 56) V, the process proceeds to step S17, and charging / discharging for recovering the deterioration of the batteries 101 and 102 described below is performed.

In step S17, the total voltage VA of the assembled battery 10 is equal to (3.726 × 56) V, that is, the deterioration of the batteries 101 and 102 in a state where the SOC of the assembled battery 10 (batteries 101 and 102) is SOC 60%. The first recovery charge / discharge CD1 is performed to recover the current.
In this step S17, the first charging current CA1 of 100A, which is the maximum current value that can be supplied to the assembled battery 10 by the converter 72, is continuously charged for 10 seconds, and then the first discharging current DA1 of 20A is charged for 50 seconds. Discharge continuously. Charging / discharging which makes this charge and discharge a pair is performed. When charging / discharging is performed with the first discharge current DA1 relatively smaller than the first charge current CA1 in this way, the lithium ion concentration SC of the excess electrolyte 130S is reduced and the internal resistance BR of the batteries 101 and 102 is reduced. The output deterioration of the batteries 101 and 102 can be recovered.
In step S17, similarly to step S13, the assembled battery 10 operates a cooling fan (not shown) for cooling the battery pack 10 to discharge the first discharge current DA1.

  Further, in the first charging current CA1, a pair of short-time charging (10 seconds) and long-time discharging (50 seconds) with the first discharging current DA1 are charged / discharged by the same first electric quantity Q1. For this reason, the SOC of the assembled battery 10 (batteries 101 and 102) after performing Step S17 can be kept at the same SOC 60% as that at the start.

After step S17 described above, in step S18, the electromotive force VP of the battery 101 is measured to determine whether or not it is smaller than the second electromotive force threshold VP2.
In the first embodiment, for example, VP2 = 7 mV (see FIG. 6). This value (7 mV) corresponds to the case where the lithium ion concentration SC of the excess electrolytic solution 130S is the second concentration threshold SC2 (= 1.1 mol / L). Further, according to FIG. 7, this value corresponds to the case where the internal resistance BR of the battery 101 is the second resistance threshold value BR2 (= 4.2 mΩ).
Therefore, when the electromotive force VP is smaller than the second electromotive force threshold VP2, it can be estimated that the lithium ion concentration SC is smaller than the second concentration threshold SC2 (see FIG. 6). Furthermore, it can be estimated that the internal resistance BR of the battery 101 is smaller than the second resistance threshold BR2 (see FIG. 7).

Therefore, if YES in step S18, that is, if the electromotive force VP is smaller than the second electromotive force threshold VP2 (VP <VP2), the process proceeds to step S30, and the assembled battery 10 is charged until the assembled battery 10 is fully charged. To do.
On the other hand, if NO in step S18, that is, if the electromotive force VP is still greater than or equal to the second electromotive force threshold VP2 (VP ≧ VP2), the process returns to step S17 and the above-described charging / discharging is performed on the assembled battery 10 (batteries 101 and 102). To do.

  Next, the processing after step S20 will be described. In step S20, as in step S10, the total voltage VA of the assembled battery 10 including the plurality of batteries 101 and the battery 102 is measured, and the SOCs of the batteries 101 and 102 forming the assembled battery 10 are estimated.

  In step S21, it is determined whether or not the total voltage VA is larger than (3.726 × 56) V. Here, if YES, that is, if the SOC of the assembled battery 10 is larger than SOC 60%, the process proceeds to step S23, and the assembled battery 10 is discharged.

  Specifically, in step S23, the assembled battery 10 is discharged at a constant current of 5A (1C), and the assembled battery 10 (batteries 101 and 102) is lowered to SOC 60%. In the vehicle 100 of the first embodiment, for example, the assembled battery 10 is discharged by operating a cooling fan (not shown) that cools the assembled battery 10.

  In step S24, the discharge in step S23 is continued until the total voltage VA of the assembled battery 10 reaches (3.726 × 56) V. When the total voltage VA of the assembled battery 10 becomes (3.726 × 56) V, the process proceeds to step S27, and charging / discharging for recovering deterioration described later is performed.

On the other hand, if NO in step S21, that is, if the total voltage VA of the assembled battery 10 is (3.726 × 56) V or less (VA ≦ (3.726 × 56) V), the process proceeds to step S22. It is determined whether or not the total voltage VA of the assembled battery 10 is equal to (3.726 × 56) V. If YES, that is, if the total voltage VA of the assembled battery 10 is equal to (3.726 × 56) V, the process proceeds to step S27.
On the other hand, if NO in step S22, that is, if the total voltage VA of the assembled battery 10 is smaller than (3.726 × 56) V (VA <(3.726 × 56) V), the process proceeds to step S25, and the assembled battery 10 is charged.

  Since the SOC of the battery pack 10 (batteries 101 and 102) is lower than SOC 60%, the battery pack 10 is charged from the external power source XV through the plug-attached cable 80 and the converter 72 in step S25. Specifically, constant current charging is performed with a charging current of 5A (1C), and the SOC of the battery pack 10 (batteries 101 and 102) is increased to SOC 60%.

  Specifically, the charging in step S25 is continued until it is determined in step S26 whether the total voltage VA of the assembled battery 10 is equal to (3.726 × 56) V. When the total voltage VA of the assembled battery 10 reaches (3.726 × 56) V, the process proceeds to step S27, and charging / discharging for recovering the deterioration of the batteries 101 and 102 described below is performed.

In step S27, the total voltage VA of the assembled battery 10 is equal to (3.726 × 56) V, that is, the deterioration of the batteries 101 and 102 in a state where the SOC of the assembled battery 10 (batteries 101 and 102) is SOC 60%. The second recovery charge / discharge CD2 is performed to recover the current.
In this step S27, the second charging current CA2 of 20A, which is 1/5 of the maximum current value that can be supplied to the battery pack 10 by the converter 72, is continuously charged for 50 seconds, and then the 100A second charging current is charged. 2 Discharge current DA2 is continuously discharged for 10 seconds. Charging / discharging which makes this charge and discharge a pair is performed. When charging / discharging is performed with the second discharge current DA2 relatively larger than the second charge current CA2 in this way, in the case where the electromotive force VP is smaller than the third electromotive force threshold VP3 (VP <VP3), surplus is obtained. The lithium ion concentration SC of the electrolytic solution 130S can be reduced, the internal resistance BR of the batteries 101 and 102 can be reduced, and the output deterioration of the batteries 101 and 102 can be recovered.
In step S27, as in step S23, the assembled battery 10 operates a cooling fan (not shown) for cooling the battery pack 10 to discharge the second discharge current DA2.

  Further, in the long-time charging (50 seconds) with the second charging current CA2 and the short-time discharging (10 seconds) with the second discharging current DA2, the same second electric quantity Q2 is charged / discharged. For this reason, the SOC of the assembled battery 10 (batteries 101 and 102) after performing step S27 can be kept at the same SOC 60% as that at the start.

After step S27 described above, in step S28, the electromotive force VP of the battery 101 is measured to determine whether it is smaller than the fourth electromotive force threshold VP4.
In the first embodiment, for example, VP4 = −5 mV (see FIG. 6). This value (−5 mV) corresponds to the case where the lithium ion concentration SC of the excess electrolyte 130S is the fourth concentration threshold SC4 (= 0.9 mol / L). Further, according to FIG. 7, this value corresponds to the case where the internal resistance BR of the battery 101 is the third resistance threshold value BR3 (= 3.8 mΩ).
Therefore, when the electromotive force VP is larger than the fourth electromotive force threshold value VP4, it can be estimated that the lithium ion concentration SC is larger than the fourth concentration threshold value SC4 (see FIG. 6). Furthermore, it can be estimated that the internal resistance BR of the battery 101 is larger than the fourth resistance threshold value BR4 (see FIG. 7).

Therefore, if YES in step S28, that is, if the electromotive force VP is smaller than the fourth electromotive force threshold VP4 (VP <VP4), the process proceeds to step S30, and the assembled battery 10 is charged until the assembled battery 10 is fully charged. To do.
On the other hand, if NO in step S28, that is, if the electromotive force VP is still greater than or equal to the fourth electromotive force threshold VP4 (VP ≧ VP4), the process returns to step S27 and the above-described charging / discharging is performed on the assembled battery 10 (batteries 101 and 102). To do.

In the first embodiment, converter 72, cable with plug 80, step S30 is an external power supply charging means, steps S4 and S5 are deterioration evaluation means, steps S17 and S27 are recovery means, PHV control device 20, converter 72, cable 80 with plug, and steps S1 to S30 correspond to charge / discharge control means, respectively.
Further, the excess electrolyte concentration detection means M1 is a deterioration detection means, steps S11 to S16, steps S21 to S26 are charge state adjustment means, steps S18 and S28 are recovery evaluation means, and step S17 is a first recovery means. Step S27 corresponds to the second recovery means, and steps S4 and S5 correspond to the selection means.

  As described above, in the vehicle 100 of the first embodiment, the batteries 101 and 102 (the assembled battery 10) that can be charged by the external power source XV are mounted, and in addition to the surplus electrolyte concentration detection unit M1, the external power source charging unit (converter 72). , Cable 80 with plug, step S30), charge / discharge control means (PHV control device 20, steps S1 to S30) including deterioration evaluation means (steps S4 and S5) and recovery means (steps S17 and S27). Therefore, it is possible to provide a vehicle 100 that can perform recovery charging / discharging using the external power source XV and easily recover output deterioration of the batteries 101 and 102 in a predetermined deterioration state.

  In the vehicle 100 of the first embodiment, the charge / discharge control means (PHV control device 20, steps S1 to S30) is subjected to deterioration evaluation means (step S4) before the charging of the batteries 101 and 102 by the external power source XV is completed. , S5) and, in some cases, recovery by recovery means (steps S17, S27). Therefore, when the output deterioration of the batteries 101 and 102 is in a predetermined deterioration state, the batteries 101 and 102 can be easily recovered by the recovery means. In addition, the external power charging means (converter 72, cable with plug 80, step S30) is connected to the batteries 101 and 102 after the evaluation of the output deterioration of the batteries 101 and 102 and, in some cases, the recovery until the recovery is completed. Charging is completed, that is, the batteries 101 and 102 can be fully charged (SOC 100%).

  Further, in the vehicle 100 of the first embodiment, the batteries 101 and 102 are set within a predetermined SOC range (SOC 55 to 65%) (SOC 60%) in advance by the charge state adjusting means (steps S11 to S16, S21 to S26). Then, recovery is performed by the recovery means (steps S17 and S27). As a result, the batteries 101 and 102 can be recovered in the same manner as usual, for example, with the same SOC at the start of recovery charge / discharge.

  Further, in the vehicle 100 according to the first embodiment, when the charge / discharge control unit includes the recovery evaluation unit (steps S18 and S28) and does not return to the predetermined recovery state, the recovery unit (steps S17 and S27) is performed again. Therefore, the vehicle 100 can reliably recover the output deterioration of the batteries 101 and 102.

  Further, the vehicle 100 according to the first embodiment includes the first recovery means (step S17) and the second recovery means (step S27) as the recovery means (steps S17 and S27). Therefore, the first recovery charge / discharge CD1 or the second recovery charge / discharge CD2 can be performed in response to the two types of deterioration modes that can occur in the batteries 101, 102, and the batteries 101, 102 can be recovered appropriately.

Further, in the first recovery means (step S17), the same first electric quantity Q1 is obtained by short-time charging (10 seconds) with the first charging current CA1 and long-time discharging (50 seconds) with the first discharge current DA1. Is charged and discharged. For this reason, for example, even if this pair of charging / discharging is repeated a plurality of times on the batteries 101, 102, the SOC of the batteries 101, 102 at the end of each time (pair) charging / discharging can be kept at the same SOC 60%.
Further, in the second recovery means (step S27), the same second electric quantity Q2 is obtained in the long-time charge (50 seconds) with the second charge current CA2 and the short-time discharge (10 seconds) with the second discharge current DA2. Is charged and discharged. For this reason, for example, even if this pair of charging / discharging is repeated a plurality of times on the batteries 101, 102, the SOC of the batteries 101, 102 at the end of each (pair) charging / discharging can be made the same SOC 60%.
Therefore, for example, the SOC of the batteries 101 and 102 gradually increases to the overcharge side or the overdischarge side while repeating the charge / discharge in the first recovery means (step S17) or the second recovery means (step S27). The charge and discharge for recovery can be safely and reliably repeated a plurality of times.

  In the first embodiment, since the deterioration detection means is the surplus electrolyte concentration detection means M1, the output deterioration of the battery 101 can be determined from the level of the lithium ion concentration SC in the surplus electrolyte 130S. The output deterioration can be easily determined without affecting the form of the element 120.

In the above, the present invention has been described with reference to the first embodiment. However, the present invention is not limited to the above-described embodiment, and it is needless to say that the present invention can be appropriately modified and applied without departing from the gist thereof.
For example, in the first embodiment, a plug-in hybrid electric vehicle that charges a secondary battery by inserting a plug into an external power supply is used. However, for example, an electric vehicle that is charged using a charger (external power supply device) installed outside. And so on. Although the battery is a wound lithium ion secondary battery, the present invention is applied to a stacked lithium ion secondary battery in which a plurality of positive plates and a plurality of negative plates are alternately stacked via separators. May be.

  Further, in the first embodiment, when the voltage application to the converter 72 is detected in step S2, the evaluation by the deterioration evaluation means (steps S4 and S5) is performed. For example, the driver inputs or in the dealer You may perform in response to the instruction | indication which an operator inputs at the time of an inspection. In the first embodiment, the evaluation by the deterioration evaluation unit is performed every time the secondary battery is charged by the external power source. However, for example, depending on the number of times of charging by the external power source counted by the counter included in the PHV control device, evaluation by the degradation evaluation means is performed intermittently, or a predetermined time from the previous evaluation is set by the timer provided in the PHV control device. In charging at the elapsed timing, the evaluation by the degradation evaluating means may be performed.

  In the first embodiment, the first measurement electrode 140 and the second measurement electrode 150 of the battery 101 are used as the deterioration detection means (excess electrolyte concentration detection means M1) in order to detect the lithium ion concentration SC of the excess electrolyte 130S. The electromotive force VP between them was measured. However, for example, a change in the retained electrolyte concentration between the electrodes of the power generation element, a change in the internal resistance of the secondary battery, or the like may be detected. Furthermore, for example, when a constant current is passed between the first measurement electrode and the second measurement electrode, it occurs between the first measurement electrode and the second measurement electrode according to the lithium ion concentration SC of the electrolytic solution 130S. You may measure the magnitude | size of the electric current which flows between the magnitude | size of a voltage and a fixed voltage by applying between a 1st measurement electrode and a 2nd measurement electrode.

Further, in the charge / discharge for recovering the degree of deterioration of the secondary battery, the amount of electricity to be charged is the same as the amount of electricity to be discharged, but each amount of electricity may be different.
Further, in the charging state adjusting means (steps S11 to S16, S21 to S26), the voltage (3.726 × 56) V corresponding to SOC 60% is compared with the total voltage VA of the assembled battery 10 as the predetermined charging state. However, for example, a voltage (one point) corresponding to any of SOC 55 to 65% which is a predetermined SOC range other than the voltage (3.726 × 56) V may be used. Further, for example, the upper limit value or the lower limit value of the voltage range corresponding to the range of SOC 55 to 65% is compared and compared, that is, the lower limit value is set for the total voltage VA corresponding to the SOC lower than the SOC 55%, and the SOC 65%. An upper limit value may be compared with the total voltage VA corresponding to a higher SOC. In this case, the discharge time or the charge time required for the charge state adjusting means can be shortened.

  Further, in the recovery means (first recovery means (step S17), second recovery means (step S27)), charging / discharging with a pair of charge and discharge is performed, and the next recovery evaluation means (steps S18, S28) is performed. However, the pair of charging / discharging may be repeated a plurality of times to proceed to the recovery evaluation means.

  In the battery 101, a filter 180 made of a porous glass plate was used. However, the movement of ions due to the concentration difference between the excess electrolyte and the reference electrolyte is prevented between the first surface and the second surface of the isolation member, and the first measurement electrode 140 and the second measurement are performed. Any member that can measure the potential between the excess electrolyte solution 130S and the reference electrolyte solution 160 by the electrode 150 may be used. For example, ceramics and resins having such characteristics may be used.

1 is a perspective view of a vehicle according to a first embodiment. It is explanatory drawing of the assembled battery mounted in the vehicle concerning Embodiment 1. FIG. 1 is a perspective view of a battery according to Embodiment 1. FIG. 2 is a partial cross-sectional view of the battery according to Embodiment 1. FIG. It is sectional drawing (AA cross section) of the battery of Embodiment 1. It is a graph which shows the relationship between the density | concentration of lithium ion in an excess electrolyte solution, and an electromotive force about the battery of Embodiment 1. It is a graph which shows the relationship between the lithium ion density | concentration in excess electrolyte solution, and internal resistance about the battery of Embodiment 1. 3 is a flowchart of the first embodiment. 2 is an explanatory diagram of Embodiment 1. FIG.

Explanation of symbols

20 PHV control device (charge / discharge control means)
72 Converter (charge / discharge control means, external power supply charge means)
80 Cable with plug (charge / discharge control means, external power supply charge means)
100 Vehicle 101, 102 Battery (secondary battery, lithium ion secondary battery)
110 battery case 120 power generation element 130S surplus electrolyte CA1 first charge current CA2 second charge current DA1 first discharge current DA2 second discharge current M1 surplus electrolyte concentration detection means (deterioration detection means)
Q1 First electric quantity Q2 Second electric quantity SC Lithium ion concentration VA Total voltage XV External power supply

Claims (8)

A vehicle equipped with a secondary battery that can be charged by an external power source installed outside the vehicle, and driven by the secondary battery,
The secondary battery is a lithium ion secondary battery,
Charge / discharge control means for controlling charge / discharge of the lithium ion secondary battery;
A deterioration detecting means for detecting output deterioration of the lithium ion secondary battery,
The charge / discharge control means includes
An external power source charging means for charging the lithium ion secondary battery with the external power source;
Deterioration evaluation means for evaluating the degree of output deterioration of the lithium ion secondary battery detected by the deterioration detection means;
And a recovery means for performing recovery charge / discharge for recovering the output deterioration of the lithium ion secondary battery when the deterioration evaluation means evaluates that the output deterioration is in a predetermined deterioration state. The vehicle according to claim 1,
The charge / discharge control means includes
Before completion of charging by the external power supply charging means, perform an evaluation by the deterioration evaluation means,
A vehicle that performs recovery by the recovery means when the deterioration evaluation means evaluates the predetermined deterioration state. The vehicle according to claim 1 or 2,
The charge / discharge control means includes
When it is evaluated by the deterioration evaluation means that the predetermined deterioration state, the charging state adjustment means for adjusting the charging state of the lithium ion secondary battery to a predetermined charging state by charging and discharging,
The vehicle in which the recovery means performs the recovery charge / discharge after the adjustment to the predetermined charging state. The vehicle according to any one of claims 1 to 3,
The charge / discharge control means includes
Including recovery evaluation means for evaluating the degree of output deterioration of the recovered lithium ion secondary battery detected by the deterioration detection means after completion of the recovery charge / discharge by the recovery means,
The recovery means is
A vehicle that performs the recovery charge / discharge again when it is evaluated by the recovery evaluation means that the predetermined recovery state has not been reached. The vehicle according to any one of claims 1 to 4, wherein
The recovery means includes
The lithium ion secondary battery is charged / discharged at least once by short-time charging with a first charging current and long-time discharging with a first discharging current relatively smaller than the first charging current. Vehicle having first recovery means for performing one recovery charge / discharge. The vehicle according to any one of claims 1 to 4, wherein
The recovery means includes
The lithium ion secondary battery is charged and discharged at least once by long-time charging with a second charging current and short-time discharging with a second discharging current that is relatively larger than the second charging current. (2) A vehicle having second recovery means for performing recovery charge / discharge. The vehicle according to any one of claims 1 to 4, wherein
The recovery means includes
The lithium ion secondary battery is charged / discharged at least once by short-time charging with a first charging current and long-time discharging with a first discharging current relatively smaller than the first charging current. 1st recovery means for performing 1 recovery charge / discharge;
The lithium ion secondary battery is charged and discharged at least once by long-time charging with a second charging current and short-time discharging with a second discharging current that is relatively larger than the second charging current. 2 recovery means for performing 2 recovery charge and discharge,
The charge / discharge control means includes
A vehicle including a selection means for selecting which of the first recovery means and the second recovery means to execute based on the evaluation of the deterioration state by the deterioration evaluation means. The vehicle according to any one of claims 1 to 7,
The deterioration detecting means includes
A vehicle which is a surplus electrolyte concentration detecting means for detecting a lithium ion concentration in an excess electrolyte stored outside the power generation element in a battery case of the lithium ion secondary battery.

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