GB2606730A

GB2606730A - Modular battery system

Info

Publication number: GB2606730A
Application number: GB2107063.6A
Authority: GB
Inventors: Tuomola Juha
Original assignee: Tanktwo Oy
Current assignee: Tanktwo Oy
Priority date: 2021-05-18
Filing date: 2021-05-18
Publication date: 2022-11-23
Anticipated expiration: 2041-05-18
Also published as: GB2606730B; WO2022243242A1; GB202107063D0

Abstract

A battery module 100 comprises a housing, a first pair of power terminals 102 located at a first surface of the housing, a second pair of power terminals 104 located at a second surface of the housing opposed to the first surface, and first and second battery stacks 111a, 111b located within the housing. Each stack comprises a plurality of battery cells connected in series between a terminal of the first pair of power terminals and a terminal of the second pair of power terminals such that the negative terminal of each battery stack is located on the same surface as the positive terminal of the other battery stack. The power terminals preferably comprise a plug or socket to facilitate direct electrical connection of the battery module to one or more identical battery modules. A PCB is preferably located within the housing, the PCB comprising the power terminals, a plurality of battery cell connectors with one or more electrical contacts connected to the plurality of battery cells, and conductive traces between the electrical contacts of the battery cell connectors and the power terminals to facilitate the series connection. The battery stacks within the housing may be connected in parallel.

Description

MODULAR BATTERY SYSTEM

Technical field

The invention relates to a battery module and a modular battery system comprising a plurality of said battery modules.

Background

Batteries are used to provide electrical power without a direct connection to an electrical power grid. Many types of batteries are known such as rechargeable lead-acid batteries commonly used in petrol cars, and lithium-ion batteries used in electric vehicles and in aircraft to provide power to control and avionics systems. Battery modules may be made up of multiple battery cells. For high voltage applications, multiple battery modules may be connected in series by, for example, clamping a jumper cable or wire at one end to the positive terminal of one battery module to the negative terminal of an identical battery. The voltage across the two unclamped terminals of the batter modules in series is equal to the sum of the voltage of each battery module. Use of a jumper cable to connect multiple batter module in this way may be hazardous as the terminals of the battery modules and the clamps may be exposed and such connections are prone to human error. Incorrectly connected batteries are a safety hazard. Such systems also require mechanical supporting structures on which to mount the plurality of battery modules to prevent them from moving relative to each other. Design and installation of such supporting structures increases the cost and complexity of systems in which multiple batteries are connected to each other.. When multiple battery modules are connected, the supporting structures and/or electrical insulators used to separate the batteries further increase the space the connected battery modules take up.

Summary

According to a first aspect of the invention there is provided a battery module comprising: a housing; a first pair of power terminals located at a first surface of the housing and a second pair of power terminals located at a second surface of the housing opposed to said first surface; and first and second battery stacks located within the housing, each stack comprising a plurality of battery cells connected in series between a terminal of said first pair of power terminals and a terminal of said second pair of power terminals such that the negative terminal of each battery stack is located on the same said surface as the positive terminal of the other battery stack.

Optionally, said power terminals each comprise a plug or a socket to allow the battery module to be directly electrically connected to one or more identical battery modules.

Optionally, the power terminals at said first surface are both a plug or are both a socket, and the power terminals at the second surface are both the other of a plug or a socket. 10 Optionally, the battery module comprises a printed circuit board (PCB) located within the housing, the PCB comprising: said power terminals; a plurality of battery cell connectors with one or more electrical contacts to electrically connect to the plurality of battery cells; and conductive traces provided between the electrical contacts of the battery cell connectors and the power terminals to facilitate said series connection.

Optionally each battery cell comprises: a cell printed circuit board (PCB) having electrical contacts thereon to connect to the electrical contacts of the battery cell connectors; and a cell housing mounted to the cell PCB.

Optionally, the cell housing is moveable between first and second positions on the cell PCB.

Optionally, the conductive traces electrically connect in parallel the electrical contacts of individual battery cell connectors of the first battery stack of the battery module to corresponding electrical contacts of the battery cell connectors of a first battery stack of the one or more identical battery modules to balance the voltage across the first stacks of the one or more identical battery modules.

Optionally, the battery module comprises a busbar mounted on a surface of the PCB, the busbar comprising contact pads at either end thereof, the busbar comprising paired contact pads at either end thereof, each pair of contact paids connected by a conductive trace, wherein one of the conductive traces is connected to one power terminal of the first pair of power terminals and one of the conductive traces is connected to the other power terminal of the first pair of power terminals; and wherein said connection between the first battery stack of the battery module with the first battery stack of the one or more identical battery modules is provided through the contact pads.

Optionally, the battery module comprises a coupler configured to directly electrically connect the conductive traces of the busbar to corresponding conductive traces of a busbar of an adjacent identical battery module of the one or more identical battery modules to balance the voltage across the first or second battery stacks of the connected battery modules.

Optionally, the housing defines a cuboid outer shape.

Optionally, the battery module comprises a jumper electrically connecting the first pair or the second pair of power terminals to each other to provide a series connection the first and second battery stacks.

Optionally, the jumper comprises a rigid, conductive bar.

Optionally, the battery cells are configured to provide a voltage of 50V between the positive and negative terminals of each battery stack.

According to a second aspect of the invention there is provided modular battery system comprising a plurality of battery modules described above, the battery modules may be plugged together by direct connection of respective pairs of power terminals.

Optionally, the battery module comprises a base electrically connected to a pair of power terminals of one of the battery modules.

Optionally, the plurality of battery modules are configured to facilitate a series connection through the plurality of first stacks, through the jumper, and through the plurality of second battery stacks.

Optionally, the plurality of battery modules are configured to facilitate a series connection through the first battery stack, the jumper, and the second battery stack of a first battery module, through the base, and through the first battery stack, the jumper, and the second battery stack of a second battery module.

Optionally, the base comprises a first busbar and a second busbar and said series connection is provided from the first busbar to the second busbar.

Optionally, the couplers electrically connect the first battery stacks of the plurality of battery modules in parallel, and connect the second battery stacks of the plurality of battery modules in parallel to balance the voltage across the battery modules.

Optionally, the base comprises a pair of plugs or sockets for connecting with the plugs or sockets of the power terminals of the plurality of battery modules.

Brief description of the drawinas

Figure la shows a perspective view of a battery module; Figure lb shows a different perspective view of the battery module of Figure la; Figure 2a shows a perspective view of the inside of the battery module of Figure la; Figure 2b shows a different perspective view of the inside of the battery module of Figure 1 a; Figure 2c is a circuit diagram of the battery module of Figure la; Figure 3 shows a perspective view of a battery cell of the battery module of Figure la; Figure 4a shows a perspective view of a modular battery system being assembled and comprising the battery module of Figure la; Figure 4b shows a perspective view of the assembled modular battery system of Figure 4a; Figure 4c shows a perspective view of an alternative configuration of an assembled modular battery system; Figure 4d shows a perspective view of an alternative configuration of an assembled modular battery system; Figure 4e shows a different perspective view of the modular battery system of Figure 4d; Figure 5 shows a perspective view of the inside of a modular battery system comprising a plurality of the battery modules of Figure la; Figure 6 shows a perspective view of a plurality of connected baseplates of a base of a modular battery system; Figure 7a shows a perspective view of a modular battery system comprising a plurality of the battery modules of Figure 1a and the base of Figure 6 being assembled; Figure 7b is a circuit diagram of the modular battery system of Figure 7a; Figure 7c is a circuit diagram of an alternative configuration of the modular battery system of Figure 7a; Figure 8a is a circuit diagram of a modular battery system; Figure 8b is an alternative configuration of the modular battery system of Figure 8a; and Figure 9 is a circuit diagram illustrating a plurality of the modular battery systems of Figures 7b or 7c.

Figure 10 illustrates seventeen modular battery system configurations.

Detailed description

Figures la and lb show different views of a battery module 100. The battery module 100 comprises a housing 101, a first pair of power terminals 102a, 102b located at a first surface 103 of the housing 101 and a second pair of power terminals 104a, 104b located at a second surface 105 of the housing 101 opposed to the first surface 103. Air vents 106 are provided through the housing 101 to allow air to circulate inside the housing 101 to provide cooling. The battery module 100 is provided with one or more optional communication interfaces 107a, 107b, such as an Ethernet port, accessible through an opening in the housing to facilitate communication with one or more components inside the housing 101. A pair of alignment holes 108 is provided at the first surface 103 of the housing 101 configured for mating engagement with a pair of alignment pins 109 at a second surface 105 of an identical, adjacent battery module. The alignment holes 108 and pins 109 allow two adjacent battery modules to be aligned and mechanically locked to each other. The housing defines a cuboid shape and is provided with an opening 110 at one or more corners to allow a parallel electrical connection to an adjacent, identical battery module to be established therethrough to balance the voltage generated by a plurality of connected identical battery modules as will be described below.

Figures 2a and 2b show perspective views of the inside of the battery module 100 of Figures la and lb. The battery module 100 comprises a first battery stack 111a and a second battery stack 111b located within the housing. Each stack comprises a plurality of battery cells 112 connected in series between a first terminal of the first pair of power terminals 102 and a second terminal of the second pair of terminals 104 such that that the negative terminal of each battery stack 111a, 111b, is located on the same said surface as the positive terminal of the other battery stack 111a, 111b. For example, the battery cells of the first battery stack 111a are connected in series between the first terminal 102a at the first surface 103 of the housing 101 and the first terminal 104a at the second surface 105 of the housing 101 whereas the battery cells of the second battery stack 111b are connected in series between the second terminal 102b at the first surface 103 and the second terminal 104b at the second surface 105. The positive terminal of the first stack 111a is thus at the same surface of the housing 101 as the negative terminal of the second stack 111b and vice versa.

The power terminals 102a, 102b, 104a, 104b each comprise a plug or a socket to allow the battery module 100 to be directly electrically and mechanically connected to one or more identical battery modules stacked on top of each other without using jumper cables and clamps to connect terminals to each other.

As will be described below, when multiple identical battery modules are connected to each other in this way, at least one of the battery modules, namely the end battery module may be provided with a jumper 126), for example a rigid, conductive bar r or a conductive trace of a jumper PCB inserted to a suitable connector on the main PCB of the battery module. This provides a series connection through the first stacks of all the battery modules, through the jumper, and through the second stacks of all the battery modules. The voltage across the other end pair of power terminals 104a, 104b, thus becomes the sum of the voltage generated by all the first stacks in series and the voltage generated by all the second stacks. This allows the total voltage output of the plurality of battery modules to be customised simply by increasing or reducing the number of battery modules connected to each other. The use of the above described jumper instead of a jumper cable with clamps improves the safety of the connected battery modules.

Additionally, as the battery modules are connected housing-to-housing, they are space efficient.

In the arrangement of Figures la, lb, 2a, and 2b, the power terminals 102a, 102b at the first surface 103 are both a socket and the power terminals 104a, 104b at the second surface 105 are both a plug.

The battery module 100 further comprises a printed circuit board (PCB) 113 located within the housing. The PCB 113 comprises the power terminals 102a, 102b, 104a, 104b and a plurality of battery cell connectors 114 with electrical contacts to electrically connect to the battery cells 112 113. Battery cell holders (not shown) may also be provided to mount the battery cells inside the battery module. The PCB 113 further comprises conductive traces provided between the electrical contacts of the battery cell connectors 114 and the power terminals 102a, 102b, 104a, 104b to facilitate the series connection through the battery cells between the power terminals in each stack. The PCB 113 may be provided with an application specific integrated circuit to control communication through the communication interfaces 107a, 107b and/or to monitor the output voltage of the stacks.

The battery module 100 may further be provided with a busbar 122 mounted on a surface of the PCB 113 on an opposite side to the battery cell connectors 114 using one or more busbar holders 123. The busbar comprises a number of conductive traces 124a, 124b, 124c to provide connection lines between contact pads 121a, 121b, 121c at either end of the busbar 122 which are exposed through said openings 110 of the housing 100. A coupler 120 may be inserted into the openings of the housing 110 to provide a continuation of the conductive traces 124a, 124b, 124c therethrough to the corresponding conductive traces of an identical busbar of an adjacent battery module. In one example, one of the conductive traces 124a of the busbar 122 is connected to one of the first pair of power terminals 102a, and one of the conductive traces 124b is connected to the other of the first pair of power terminals. A third conductive trace 124c may also be provided. Thus, when multiple battery modules are positioned adjacent to each other and their respective busbars 122 are joined together with couplers 120, all of the first stacks of the multiple battery modules may be connected in parallel to each other and all of the second stacks of the battery modules may be connected in parallel to each other to balance the voltage across the first and second stacks of multiple battery modules. The coupler 120 is thus provided with contact pads (not shown) configured to contact and electrically connect to the corresponding contact pads 121a, 121b, 121c on the busbar 122.

The PCB 113 may also be provided with a mounting structure 125 to secure the PCB to the inside of the housing 100.

Figure 2c is a circuit diagram of a battery module 100 Figures la and lb. The jumper 126 is shown in Figure 2c connected at the terminals of the first and second stacks 111a and 111b. When the jumper 126 is connected, a series connection is established between the pair of second power terminals 104a, 104b through the first battery stack 111a, through the jumper 126, and through the second battery stack 111b. The voltage across the pair of second power terminals 104a, 104b is thus the sum of the voltage provided by the first and second battery stacks 111a, 111b. A neutral or ground line 127 running parallel to the battery stacks may also be provided.

Figure 3 shows a perspective view of an exemplary configuration of a battery cell that may be used as one of the battery cells 112 of Figures 2a and 2b. The battery cell 112 comprises a cell printed circuit board (PCB) 115 having electrical contacts 116 thereon, for example on one or more tabs 115a of the cell PCB, to contact and thus electrically connect to the electrical contacts of the battery cell connectors 114 when the battery cell 112, and in particular the tabs 115a of the cell PCB 115 of the battery cell 112, are inserted into a battery cell holder 114. The battery cell 112 further comprises a cell housing 117 mounted to the cell PCB 115 for example using two clips 118. The cell housing 117 has a rectangular or square shape (although other shapes are also envisaged) and houses the electrochemical components of the battery cell 112 whose reaction generates a voltage across the battery cell 112. For example, when the battery cell 112 is a rechargeable lithium-ion polymer battery, the cell housing 117 houses lithium-ion polymer components. Conductive traces (not shown) are provided on the cell PCB 115 to electrically connect the lithium-ion polymer components inside the cell housing 117 to the electrical contacts 116 on the tabs 115a of the cell PCB 115, one of which is a positive terminal and one of which is a negative terminal of the battery cell 112.

The clips 118 allow the cell housing 117 to be moved between first and second positions on the cell PCB 115 as indicated by the arrow 119 in Figure 3. This allows the battery cell 112 to be customised for different battery module layouts and used on differently sized cell PCBs 115. For example, when a cell PCB 115 has a higher number of tabs 115a and electrical contacts 116 than is shown in Figure 3, the cell housing 117 may be shifted further along the cell PCB 115 to provide more space for additional tabs 115a and electrical contacts 116.

When the tabs 115a of the battery cells 112 are inserted into the battery cell connectors 114, for example arranged as is shown in Figures 2a and 2b where the battery cell connectors 114 of each battery stack 111a, 111b are positioned in a line on the surface of the PCB 113, the cell housings 117 are positioned towards an axial centre line of the PCB 113 of the battery module 100 to provide a space efficient and compact layout. If the battery cells 112 are used in a battery module 100 that has a narrower PCB 113, the cell housing 117 may be shifted along the cell PCB 115 (as indicated by the arrow 119 in Figure 3) to allow the cell PCBs 115 to be positioned closer together when mounted to the battery module PCB 113 without the cell housings 117 touching.

The configuration of Figure 3 is optional. In particular, the battery cell 112 may alternatively be connected directly to the PCB by plugging cell tabs directly into the the battery cell connector 114 without a cell PCB 115.

Figures 4a and 4b show perspective views of a modular battery system 400. Figure 4a illustrates two identical battery modules 100a and 100b and a jumper 401 being connected as indicated by the arrows 401 and 402. In particular, the plug power terminals of one of the first battery module 100a are connected to the socket power terminals of the second battery module 100b. The plugs of the jumper 401 connect the socket terminals of the first battery module 100a to each other. This results in a modular battery system 400 having the arrangement of Figure 4b. Whilst only two battery modules are shown in Figure 4b, it is envisaged that the modular battery system 400 may have any number of identical battery modules.

The modular battery system 400 of Figure 4b further comprises a base 404 comprising first and second busbars 405a, 405b and a mounting plate 406 having a pair of plugs or sockets thereon to receive the corresponding plugs or sockets of one of the battery modules 100b. The first and second battery modules 100a, 100b are arranged to provide a series connection from the first basbar 405a to the second busbar 405b through the first battery stacks of the first and second battery modules, through the jumper 401, and through the second battery stacks of the first and second battery modules. The arrow 407 shown in Figure 4b illustrates such a series connection. The voltage across the busbars 405a, 405b is thus the sum of the voltage of all of the battery stacks. For example, if each battery stack provides 50V and the two battery modules 100a, 100b each have two stacks then the voltage across the first and second busbars 405a, 405b is 200V. Each additional battery module added to the modular battery system in this arrangement will add 100V to the voltage across the first and second busbars 405a, 405b of the base 404. Couplers 120 are optionally provided should additional identical battery modules be connected in parallel to the first and second battery modules 100a, 100b. The first and second busbars 405a, 405b may be electrically connected to an external device to power it. The first and second busbars 405a, 405b may be omitted for low current applications wherein the series connection is instead provided between end connectors (not shown in Figure 4a) of the base 404.

Figure 4c shows a perspective view of an alternative configuration of a modular battery system 400 comprising a plurality of the battery modules 100a-100c of Figure la. Figure 4c illustrates how couplers 120 may be used to connect the battery modules in parallel with each other and how three or more battery modules may be positioned adjacent each other on the base 404. In Figure 4c, the series connection between the first and second busbars 405a, 405b is made through the first stack, the jumper (not shown), and the second stack of the first battery module 100a, through the baseplate of the base, through the first stack, the jumper (not shown), and the second stack of the second battery module 100b, through the baseplate again, through the first stack, the jumper (not shown) and the second stack of the third battery module 100c, and finally to the second busbar 405b. Such an arrangement is also illustrated in the circuit diagram of Figure 7c.

Figures 4d and 4e show alternative perspective views of an alternative configuration of a modular battery system 400 comprising a plurality of battery modules 100a-100d of Figure la. In Figures 4d and 4e, the series connection between the first and second busbars 405a, 405b is made through the first stack, the jumper (not shown), and the second stack of the first battery module 100a, through a first baseplate 406a of the base, through the first stack, the jumper (not shown), and the second stack of the second battery module 100b, through a busbar connecting the first baseplate 406a to a second baseplate 406b, through the first stack, the jumper (not shown) and the second stack of the third battery module 100c, through the second base 406b again, through the first stack, the jumper (not shown) and the second stack of the fourth battery module 100d, and finally to the second busbar 405b. A similar arrangement is also illustrated in the circuit diagram of Figure 7c.

Figure 5 shows a perspective view of a modular battery system 500 having four identical battery modules 100a, 100b, 100c, 100d connected to each other. The housing and base are not shown in Figure 5 although it is envisaged they are present. The battery modules are arranged in two columns of two batteries. Two identical series circuits indicated by the arrows 501a, 501b are provided by pairs of the battery modules plugged into each other with end power terminals each connected by a jumper 502a, 502b, which may be arranged internally. As described above, optional couplers 503 are provided to connect the power terminals of the first or second battery stacks of one battery module 100a, 100b in parallel to the corresponding terminals of the first or second battery stacks of an adjacent identical battery module 100c, 100d to balance the voltage across the battery modules 100a, 100b, 100c, 100d. Figure 5 also shows where couplers 503 would be positioned should additional battery modules be connected adjacent to the battery modules 100a, 100b, 100c, 100d.

Figure 6 shows a perspective view of a plurality of connected base plates 601a, 601b, 601c of a base 600 for use in a modular battery system such as that shown in Figure 5. The base plates 601a, 601b, 601c are daisy chained together with suitable end connectors 602a, 602b, 602c, 603a, 603b, 603c at each end thereof. The end connectors 602a, 602b, 602c, 603a, 603b, 603c may be for example matching plugs and sockets.

For low current applications of the modular battery system, one or more of the end connectors 602a, 603c may connected to an external device to power it. For high current applications, first and second parallel busbars 604a, 604b are provided running alongside and electrically connected to respective plugs or sockets of the base plates 601a, 601b, 601c using, for example, a bar connector 605. The arrangement of daisy chained baseplates of Figure 6, allows multiple stacks of identical battery modules to be connected to each other in various arrangements as will be described below. The above described voltage balancing using for example the couplers 503 for Figure 5 may also or instead be achieved using traces 606a, 606b, 606c on the baseplates 601a, 6061b, 6061c, depending on the configuration used.

Figure 7a shows a perspective view of a modular battery system 700 comprising a plurality of battery modules 701 in six connected columns 702a, 702b, 702c, 702d, 702e, 702f of two battery modules each for example in a similar manner to that shown Figure 5. The housing is not shown but is envisaged to be present. The battery module at one end of each column is provided with a jumper across the end pair of power terminals and the battery module at the other end of the column is plugged into a base plate of a base 600 such as that of Figure 6 as indicated by the arrows 701. The jumper may be arranged internally in the manner shown in Figures 2b, 2c, and 5. The arrangement of Figure 7a is exemplary only and additional battery modules may be added to or removed from the modular battery system 700 to increase or decrease the voltage output of the system.

Figure 7b is a circuit diagram of a modular battery system 700 such as that of Figure 7a showing the plurality of identical battery modules 701a-701i arranged in columns 702a- 702c with couplers 704 provided to connect the power terminals of the battery modules in parallel to balance the voltage across the battery modules. Each column 702a-702c has a jumper to connect the end pair of power terminals to facilitate the series circuit of each column in the manner as shown in Figure 5. Each column is mounted to and electrically connected to a respective baseplate 601a-601c of the base 600. The series circuit of each column connects the first and second busbars of the base. Whilst only three columns of three identical modular batteries are shown in Figure 7b, the dotted lines indicate additional columns and/or battery modules may be added to or removed from the modular battery system 700 to increase or decrease the output voltage of the system 700.

Figure 7c is a circuit diagram of an alternative configuration 705a of the modular battery system 700. The modular battery system of Figure 7c comprises a plurality of identical battery modules 701a-701c mounted to corresponding base plates 601a-601c of a base 600. Each battery module 701a-701c has a jumper to connect the pair of power terminals at one end of the battery module. Unlike in Figure 7b, the battery terminals are connected in series to each other through the base 600. The series circuit thus connects the first and second busbars of the base 600 through the first stack, the jumper, and the second stack of the first battery module 701a, through the base 600 without connecting to the busbars, through the first stack, the jumper, and the second stack of the second battery module 701b, through the base again, and finally through the first stack, the jumper and the second stack of the third battery module 701c before connecting to the second busbar to complete the circuit. In this alternative arrangement, the voltage across the first and second busbars is again the sum of the voltage of all of the stacks of the battery modules. It is envisaged that a plurality of such configurations 705b-705c may be provided on a base 600 as shown in Figure 7c. The dotted lines indicate that additional battery modules may be added or removed to the configurations 705a-705c and any number of such configurations may be added or removed to customise the output voltage.

Figure 8a is a circuit diagram of a modular battery system 800 comprising a plurality battery stacks 801a-801i of identical battery modules such as those described above, represented in columns 802, 803, 804. Each column represents a series circuit such as the series circuits described in Figures 7b and 7c. The columns 802, 803, 804 are connected in parallel through a base, for example the base of Figure 6. Whilst only three columns and are shown in Figure 8a, the dotted lines indicate additional battery modules may be provided to add additional series circuits to the modular battery system. The modular battery system 800 may be connected at its positive and negative terminals 805, 806 (for example the ends of the first and second busbars of the base or the end connectors of the one or more of the baseplates) to an external device to power it.

Figure 8b is a circuit diagram identical to that of Figure 8a except that couplers 807a-807g are connected in parallel between the battery stacks as described above with reference to Figure 5 to balance the voltage across the battery stacks of the plurality of battery modules.

Figure 9 illustrates a modular battery system 900 comprising a plurality 700a-700f of the systems 700 of Figures 7b-7c. Each system has its own base 600a-600c with corresponding positive and negative output terminals, for example the ends of the first and second busbars of each base. The dotted line indicates additional systems may be added or removed to increase or decrease the number of output terminals available to connect to one or more external devices to power them.

Figure 10 illustrates seventeen exemplary different configurations (a)-(q) of battery systems comprising one or more of the battery modules described herein. In example configuration (a), one battery module is provided that outputs 100V. In example configurations (b)-(e), two battery modules are provided that together output 200V. In example configurations (f)-(h), three battery modules are provided that together output 300V. In example configurations (j)-(g), four battery modules are provided that together output 400V. It is envisaged that these output voltages are exemplary only and the output voltage of each battery module will depend on the voltage output by the battery cell stacks in each battery module.

The skilled person will be able to envisage other battery modules, modular battery systems and configurations thereof without departing from the scope of the appended claims. In particular, it is noted that one or more features included in one or more drawings may be integrated into the battery modules or battery modular systems shown in other drawings, as will be appreciated by the skilled person.

For example, it is envisaged that any combination of plugs and sockets may be used as the pairs of power terminals at the first and second surfaces. For example both terminals at the first surface may be plugs while the terminals at the second terminals are sockets or vice versa. Alternatively, there may be one of each of a plug or socket at the first surface and the opposite arrangement at the second surface to allow mating engagement between them.

For example, it is envisaged that the alignment holes may have any shape or cross section and the alignment pins will be shaped accordingly to match the alignment holes. It is also envisaged that any number of alignment holes and corresponding pins may be used to provide said alignment and mechanical locking of the battery modules to each other. The alignment holes and pins may also be used to provide a safety interlock whereby the battery module is configured to prevent the terminals from being live unless the alignment pins are detected to be present in the alignment holes.

For example, it is envisaged that the battery cells may be mounted to the cell PCB using any number of clips or other holding structures, for example one, two, three, four or more. Similarly, the number of electrical contacts may be any number depending, for example, on the voltage of the battery cell. For example, whilst Figure 3 shows three electrical contacts, one, two, three, four or more may also be provided. Additionally, for increased battery cell interchangeability between battery module designs, it is not necessary for all of the electrical contacts of the battery cell to be in contact with an electrical contact in the battery cell holder. This allows the battery cell to be used in any battery module regardless of the number of electrical contacts in the battery cell holder. Further, it is envisaged that any number of battery cells may be used in each of the stacks to achieve a desired voltage. For example, each stack may generate 50V. Thus when a jumper connects the pair of power terminals at the same surface to put the two stacks in series connection, the voltage across the pair of power terminals at the opposite surface will be 100V. If additional battery modules are connected in series, each additional battery module generates an additional 100V across the end pair of terminals opposite the jumper.

It will thus be appreciated that the battery module and modular battery system of the present disclosure provide a safe and reliable way to power a device that may be used in many different, customisable configurations that can be grown or shrunk in all three dimensions by adding or removing battery modules. For example, as all connections between battery modules are made housing-to-housing, PCB-to-PCB, no external mid-voltage busbars are needed between battery modules making the installation and design of the modular battery system much faster and simpler. In addition as no mid-voltage busbars are needed between battery modules, many complex layers of insulators and joining between the housings are not required. This makes a space saving per battery module of around 5% in width and height, and 10% in depth compared to when mid-voltage busbars and/or complex layers of insulator are required between battery modules. This equates to around a 20% volumetric space saving. In addition, as all of the configurations described herein may be built from the same, identical battery module and baseplates, manufacturing and storage is simplified and thus made cheaper and more efficient. Further, as the base of the modular battery system carries all the voltages, including any mid-voltages between columns of battery modules, diagnostics and maintenance is made easier as the voltage at different points in each of the series circuits may be conveniently accessed from the base.

It is envisaged that one exemplary modular system may be built of a plurality of 100V battery modules each comprising two 50V battery stacks. Each set of four battery modules able to provide a 400V output voltage and a current of between 24A-80A. In such an arrangement, each battery stack comprises 28 Li-Po pouch cells. The cells are detachable from the PCB of the battery modules for easy replacement. The PCB of the battery module may also comprise a processor to control and/or bypass individual cells and may comprise a memory to store individual battery cell data. The weight of each battery module is envisaged to be around 7kg and have a size of around 250 x 200 x 125mm. In this exemplary configuration, it is envisaged the battery modules may be arranged in 17 different ways to provide a modular battery systems outputting between 100V-400V.

For example, whilst the jumper has described herein to be connected on the outside of the housing, it is also envisaged that the jumper may be provided inside the housing and may be connected or disconnected in response to the actuation of a mechanical button or switch provided on the outside of the housing.

Claims

CLAIMS: 1. A battery module comprising: a housing; a first pair of power terminals located at a first surface of the housing and a second pair of power terminals located at a second surface of the housing opposed to said first surface; and first and second battery stacks located within the housing, each stack comprising a plurality of battery cells connected in series between a terminal of said first pair of power terminals and a terminal of said second pair of power terminals such that the negative terminal of each battery stack is located on the same said surface as the positive terminal of the other battery stack.
2. The battery module of claim 1, wherein said power terminals each comprise a plug or a socket to facilitate direct electrical connection of the battery module to one or more identical battery modules.
3. The battery module of claim 1, wherein the power terminals at said first surface are both a plug or are both a socket, and the power terminals at the second surface are both the other of a plug or a socket.
4. The battery module of any preceding claim comprising a main printed circuit board (PCB) located within the housing, the main PCB comprising: said power terminals; a plurality of battery cell connectors with one or more electrical contacts to electrically connect to the plurality of battery cells; and conductive traces provided between the electrical contacts of the battery cell connectors and the power terminals to facilitate said series connection.
5. The battery module of claim 4, wherein each battery cell comprises: a cell printed circuit board (PCB) having electrical contacts thereon to connect to the electrical contacts of the battery cell connectors; and a cell housing mounted to the cell PCB.
6. The battery module of claim 5, wherein the cell housing is moveable between first and second positions on the cell PCB.
7. The battery module of any of claims 4 to 6, wherein the conductive traces electrically connect in parallel the electrical contacts of battery cell connectors of the first battery stack of the battery module to corresponding electrical contacts of the battery cell connectors of a first battery stack of the one or more identical battery modules to balance the voltage across the first stacks of one or more identical battery modules.
8. The battery module of claim 7 and comprising a busbar mounted on a surface of the main PCB, the busbar comprising paired contact pads at either end thereof, each pair of contact pads connected by a conductive trace, wherein one of the conductive traces is connected to one power terminal of the first pair of power terminals and one of the conductive traces is connected to the other power terminal of the first pair of power terminals; and wherein said connection between the first battery stack of the battery module with the first battery stack of the one or more identical battery modules is provided through the contact pads.
9. The battery module of claim 8 and comprising a coupler configured to directly electrically connect the conductive traces of the busbar to corresponding conductive traces of a busbar of an adjacent identical battery module of the one or more identical battery modules to balance the voltage across the first or second battery stacks of the connected battery modules.
10. The battery module of any preceding claim, wherein the housing defines a substantially cuboid outer shape.
11. The battery module of any preceding claim comprising a removable jumper electrically connecting the first pair or the second pair of power terminals to each other to provide a series connection the first and second battery stacks.
12. The battery module of claim 11, wherein the jumper comprises a rigid, conductive bar.
13. The battery module of any preceding claim, wherein battery cells are configured to provide a voltage of approximately 50V between the positive and negative terminals of each battery stack.
14. A modular battery system comprising a plurality of the battery modules of any of claims 1 to 13.
15. The modular battery system of claim 14 wherein the battery modules are plugged together by direct connection of respective pairs of power terminals.
16. The modular battery system of claim 14 or 15 comprising a base electrically connected to a pair of power terminals of one of the battery modules.
17. The modular battery system of claim 16 when dependent on claims 11 or 12, wherein the plurality of battery modules are configured to facilitate a series connection through the plurality of first stacks, through the jumper, and through the plurality of second battery stacks.
18. The modular battery system of claim 16 when dependent on claims 11 or 12, wherein the plurality of battery modules are configured to facilitate a series connection through the first battery stack, the jumper, and the second battery stack of a first battery module, through the base, and through the first battery stack, the jumper, and the second battery stack of a second battery module.
19. The modular battery system of claims 17 or 18, wherein the base comprises a first busbar and a second busbar and said series connection is provided from the first busbar to the second busbar.
20. The modular battery of system of any of claims 14 to 19 when dependent on claim 9, wherein the couplers electrically connect the first battery stacks of the plurality of battery modules in parallel, and connect the second battery stacks of the plurality of battery modules in parallel to balance the voltage across the battery modules.
21. The modular battery system of any of claims 14 to 20 when dependent on claim 2, wherein the base comprises a pair of plugs or sockets for connecting with the plugs or sockets of the power terminals of the plurality of battery modules.Amendments to the claims have been filed as folio CLAIMS: 1. A kit of parts for assembly into a modular battery system, the kit of parts comprising: a plurality of battery modules, each module comprising: a housing defining a cuboid shape and having an opening at one or more corners, the opening configured to facilitate a parallel electrical connection to an adjacent, identical battery module; a first pair of power terminals located at a first surface of the housing and a second pair of power terminals located at a second surface of the housing opposed to said first surface; and first and second battery stacks located within the housing, each stack comprising a plurality of battery cells connected in series between a terminal of said first pair of power terminals and a terminal of said second pair of power terminals such that the negative terminal of each battery stack is located on the same said C\I surface as the positive terminal of the other battery stack; C\I a jumper configured to electrically connect a pair of the power terminals of one of the CO battery modules to each other to provide a series connection between the first and CD second battery stacks of the battery module; and CO 20 a base configured to electrically connect pairs of power terminals of one or more adjacent CD battery modules.2. The kit of parts of claim 1, wherein said power terminals each comprise a plug or a socket to facilitate direct electrical connection of the battery module to one or more identical battery modules.3. The kit of parts claim 1, wherein the power terminals at said first surface are both a plug or are both a socket, and the power terminals at the second surface are both the other of a plug or a socket.4. The kit of parts of any preceding claim, wherein the battery module comprises a main printed circuit board (PCB) located within the housing, the main PCB comprising: said power terminals; a plurality of battery cell connectors with one or more electrical contacts to electrically connect to the plurality of battery cells; and conductive traces provided between the electrical contacts of the battery cell connectors and the power terminals to facilitate said series connection.5. The kit of parts of claim 4, wherein each battery cell comprises: a cell printed circuit board (PCB) having electrical contacts thereon to connect to the electrical contacts of the battery cell connectors; and a cell housing mounted to the cell PCB.6. The kit of parts of claim 5, wherein the cell housing is moveable between first and second positions on the cell PCB.7. The kit of parts of any of claims 4 to 6, wherein the conductive traces electrically connect in parallel the electrical contacts of battery cell connectors of the first battery stack of the battery module to corresponding electrical contacts of the battery cell connectors of a first battery stack of the one or more identical battery modules to balance C\I the voltage across the first stacks of one or more identical battery modules. C\ICO 8. The kit of parts of claim 7, wherein the battery module comprises a busbar CD mounted on a surface of the main PCB, the busbar comprising paired contact pads at CO 20 either end thereof, each pair of contact pads connected by a conductive trace, CD wherein one of the conductive traces is connected to one power terminal of the first pair of power terminals and one of the conductive traces is connected to the other power terminal of the first pair of power terminals; and wherein said connection between the first battery stack of the battery module with the first battery stack of the one or more identical battery modules is provided through the contact pads.9. The kit of parts of claim 8 comprising a coupler configured to directly electrically connect the conductive traces of the busbar to corresponding conductive traces of a busbar of an adjacent identical battery module of the one or more identical battery modules to balance the voltage across the first or second battery stacks of the connected battery modules.10. The kit of parts of any preceding claim, wherein the jumper comprises a rigid, conductive bar.11. The kit of parts of any preceding claim, wherein battery cells are configured to provide a voltage of 50V between the positive and negative terminals of each battery stack.12. The kit of parts of any preceding claim wherein the battery modules are plugged together by direct connection of respective pairs of power terminals.13. The kit of parts of any preceding claim, wherein the plurality of battery modules are configured to facilitate a series connection through the plurality of first stacks, through the jumper, and through the plurality of second battery stacks.14. The kit of parts of any preceding claim, wherein the plurality of battery modules C\I are configured to facilitate a series connection through the first battery stack, the jumper, C\I and the second battery stack of a first battery module, through the base, and through the CO first battery stack, the jumper, and the second battery stack of a second battery module.CDCO 20 15. The kit of parts of claims 13 or 14, wherein the base comprises a first busbar and CD a second busbar and said series connection is provided from the first busbar to the second busbar.16. The kit of parts of any of any preceding claim, wherein the couplers electrically connect the first battery stacks of the plurality of battery modules in parallel, and connect the second battery stacks of the plurality of battery modules in parallel to balance the voltage across the battery modules.17. The kit of parts of any of claims 2 to 16, wherein the base comprises a pair of plugs or sockets for connecting with the plugs or sockets of the power terminals of the plurality of battery modules.18. A modular battery system assembled from the kit of parts of any preceding claim.