Battery module and battery module stack

Abstract

A battery module is described, comprising: a cell housing for accommodating a plurality of battery cells; and a cooling assembly. The cooling assembly includes a cooling channel that extends from a hole in a first side of the battery module to a hole in a second side of the battery module. The cooling channel is positioned such that heat generated within the cell housing can be transferred to a cooling fluid that flows from the first side of the battery module to the second side of the battery module via the cooling channel. A battery module stack including a plurality of such battery modules is also described. The battery modules are arranged in a stacked structure such that the cooling channels of at least one battery module are aligned with the cooling channels of at least one adjacent battery module.

Description

Technical Field

[0001] The present disclosure relates to a battery module and a battery module stack including a plurality of battery modules. Background Art

[0002] One type of rechargeable battery is a lithium-ion battery having a multi-layer structure, which includes a positive electrode activated by various mixed oxides or olivines, a negative electrode activated by special carbon, and a separator fully immersed in an organic electrolyte. The battery is usually housed in a casing to form a battery module. Under normal operating conditions, electrical energy is converted into chemical energy and stored as chemical energy during charging, and the stored chemical energy is converted into electrical energy during discharging. More specifically, during charging, lithium in the positive electrode is ionized and moves layer by layer to the negative electrode; during discharging, the ions move to the positive electrode and return to their original compounds. A plurality of lithium-ion battery modules can be mounted on a rack assembly together with a control module for controlling the battery modules to form a battery pack.

[0003] Various different types of racks can be used to store and transport interconnected battery modules. In its simplest form, the rack can include a frame having a plurality of slots into which the battery modules are inserted. Then, power and cooling lines can be connected to the battery modules. In another variant, the rack can include a backplane that houses power connections. The battery modules (whose power connectors are located at the rear of the module) are inserted into slots and directly into the backplane.

[0004] However, generally, the use of a rack complicates the battery pack. For example, using a rack to house the battery modules increases the number of components forming the battery pack, thus increasing the manufacturing cost of the battery pack. Additionally, a rack employing a backplane may be prone to alignment problems occurring between the power connectors of the battery modules and the power lines of the backplane.

[0005] Therefore, there is still a need in the art to provide a battery module that enables simpler and more efficient storage and transportation of a plurality of interconnected battery modules. Summary of the Invention

[0006] In a first aspect of the present disclosure, there is provided a battery module including: at least one unit casing for housing a plurality of battery cells; and a cooling assembly: the cooling assembly includes a cooling channel that extends from a hole in a first side of the battery module to a hole in a second side of the battery module; and the cooling assembly is positioned such that heat generated within the unit casing can be transferred to a cooling fluid that flows from the first side of the battery module to the second side of the battery module via the cooling channel. Thus, a first outer side of the module can be fluidly connected to a second outer side of the module.

[0007] The battery module may further include an exhaust assembly, which includes an exhaust passage extending from a hole in one side of the battery module to a hole in another side of the battery module; and an exhaust port extending from the unit housing to the exhaust passage. The exhaust passage may extend from a hole in the first side of the battery module to a hole in the second side of the battery module.

[0008] The battery module may further include a seal that seals the exhaust port and is configured to open in response to the pressure within the unit housing reaching a critical pressure, thereby allowing exhaust to flow from the unit housing to the exhaust passage. The seal may be configured to open in response to a thermal runaway occurring within the unit housing.

[0009] The exhaust port may extend through the cooling channel.

[0010] The cooling assembly may be located between the unit housing and the exhaust assembly.

[0011] At least one unit housing may include a first unit housing and a second unit housing on respective sides of the battery module, and wherein the cooling channel may extend between the first unit housing and the second unit housing. The cooling channel may extend along the length of each of the first unit housing and the second unit housing.

[0012] The battery module may further include a radiator disposed on one or more sides of the battery module. The radiator may include one or more cooling fins. The radiator may include a spread plate or a heat pipe for guiding heat to the cooling assembly.

[0013] The battery module may further include at least one first locking member extending from an upper edge or a lower edge of the battery module. The battery module may further include at least one first locking member extending from an upper corner or a lower corner of the battery module.

[0014] The battery module may further include at least one second locking member located at an edge or a corner of the battery module that is opposite to the edge or corner from which at least one first locking member of the battery module extends.

[0015] The battery module may further include a power and communication assembly that includes one or more of a circuit and a processor, the processor being configured to monitor one or more battery cells housed within the battery module. The power and communication assembly may be located at a first end of the battery module, and the cooling assembly may be located at an opposite second end of the battery module. The power and communication assembly may be located at the front end of the battery module, and wherein the cooling assembly is located at the rear end of the battery module. Thus, most of the potentially repairable components may be located at the front of the battery module, enabling easy access to them.

[0016] The power and communication components may include power pins that are movable between a retracted position and an extended position. In some embodiments, in a first "retracted" position, the power pins may be retracted within the battery module, and in a second "extended" position, the power pins may extend outside the battery module. In some embodiments, the power pins may be within the battery module in both their retracted position and their extended position. The battery module may also include a switch configured to move the power pins between the first position and the second position when actuated. Thus, by retracting the power pins, the battery module can be made safer for handling / transport. Additionally, retracting the power pins interrupts the power circuit in an assembled stack of modules, for example, in order to service components of the module.

[0017] The power and communication components may also include a power socket located on an outer surface of the battery module. The power socket may be located on the lower side of the battery module, and the power pins may extend out of the upper side of the battery module when in the second position. The power pins and the power socket may be directly opposite each other.

[0018] The battery module may also include a removable panel on a front surface of the battery module for access to one or more components of the power and communication components.

[0019] The power and communication components may also include a first optical communication port on one side of the battery module and a second optical communication port on another side of the battery module.

[0020] The power and communication components may also include a wireless communication module for communicating with one or more other battery modules.

[0021] The battery module may also include a heat sink adjacent to the unit housing. The heat sink may be fluidly connected to a cooling channel and the exterior of the battery module; and heat generated within the unit housing can be transferred out of the battery module by being transferred to a cooling fluid that flows from the cooling channel through the heat sink to the exterior of the battery module. The heat sink may include a fluid flow path that extends from the cooling channel into the heat sink via one or more inlets and returns from the heat sink to the cooling channel via one or more outlets; and heat generated within the unit housing can be transferred out of the battery module by being transferred to a cooling fluid that enters the cooling channel from a first side of the battery module, flows into the fluid flow path, returns to the cooling channel, and exits the cooling channel to a second side of the battery module.

[0022] One or more of the cooling channel, the exhaust channel, and the power socket may extend through the heat sink.

[0023] The cooling fluid may include one or more of the following: forced air, a liquid coolant, or air flowing by convection.

[0024] The battery module may further include one or more male connectors on one of the top and bottom sides of the battery module, and one or more female connectors on the other of the top and bottom sides of the battery module, and at least one of the connectors includes a tapered portion. For example, one or more of the female connectors may include a tapered portion.

[0025] One or more of the male connectors may include at least one first locking member, and one or more of the female connectors may include at least one second locking member.

[0026] One or more of the male connectors may include one or more power pins, and one or more of the male connectors may include one or more power sockets.

[0027] In another aspect of the present invention, there is provided a battery module stack including a plurality of battery modules, each battery module including: at least one cell housing for accommodating a plurality of battery cells; and a cooling assembly including a cooling channel: the cooling channel extends from a hole in a first side of the battery module to a hole in a second side of the battery module; and the cooling channel is positioned such that heat generated within the cell housing can be transferred to a cooling fluid that flows through the cooling channel from the first side of the battery module to the second side of the battery module, wherein the battery modules are arranged in a stacked structure such that the cooling channels of at least one battery module are aligned with the cooling channels of at least one adjacent battery module.

[0028] The battery module stack may further include a base at the bottom of the stacked structure; and an air delivery device configured to cause air to flow through the base via the cooling channels and through the cooling channels of the stacked battery modules, the cooling channels being formed within the base and in fluid communication with the cooling channels of the stacked battery modules.

[0029] Each battery module may further include: an exhaust assembly including an exhaust channel extending from a hole in a first side of the battery module to a hole in a second side of the battery module; and an exhaust port extending from the cell housing to the exhaust channel; and the exhaust channels of at least one battery module may be aligned with the exhaust channels of at least one adjacent battery module. The base may include an exhaust outlet in fluid communication with the exhaust channels of the stacked battery modules.

[0030] Advantageously, the integrated nature of the cooling and / or exhaust assemblies with the battery module may allow the module stack to be assembled without a dedicated backplane. A backplane may refer to a single structure that houses the electrical connections of the battery modules, and to which multiple battery modules are connected or "plugged in".

[0031] The battery module stack may further include a group controller communicatively coupled to the battery modules and operable to control the operation of the battery modules. The group controller may be stacked with the battery modules.

[0032] The battery module stack may further include a cover positioned on top of the stacked structure such that the cooling channels of the uppermost battery module of the stacked structure are sealed.

[0033] The battery module stack may further include a stabilizing mechanism configured to apply a compressive force to the stacked structure to stabilize the stacked structure.

[0034] The stabilizing mechanism may include one or more cables or rods (such as solid rods) attached to the cover and attached to one or more points at least as low as the lowermost battery module of the stacked structure.

[0035] Additionally, in the case of a liquid cooling module, the cover may terminate the coolant manifold, the cover may house a "jumper" bus bar for returning current towards the base of the stack, and the cover may be jumper-connected for returning current towards the base of the stack.

[0036] Each battery module may further include one or more locking members that engage corresponding locking members of one or more of the adjacent upper and adjacent lower battery modules. The one or more locking members of the battery module may be configured to engage the corresponding locking members of the adjacent upper battery module in response to another battery module being stacked on top of the adjacent upper battery module.

[0037] In another aspect of the present disclosure, a method of assembling a battery module stack by stacking a plurality of battery modules to form a stacked structure is provided, wherein each battery module includes: at least one cell housing for accommodating a plurality of battery cells; and a cooling assembly: the cooling assembly includes cooling channels extending from holes in a first side of the battery module to holes in a second side of the battery module; and the cooling assembly is positioned such that heat generated within the cell housing can be transferred to a cooling fluid that flows through the cooling channels from the first side of the battery module to the second side of the battery module; and wherein the stacked structure is configured such that the cooling channels of at least one battery module are aligned with the cooling channels of at least one adjacent battery module.

[0038] The method may further include positioning a cover on top of the stacked structure such that the cooling channels of the uppermost battery module of the stacked structure are sealed. The method may further include using a stabilizing mechanism to apply a compressive force to the stacked structure to stabilize the stacked structure.

[0039] In another aspect of the present invention, a method of using a battery module stack is provided, the battery module stack including a plurality of battery modules, each battery module including: at least one cell housing for accommodating a plurality of battery cells; a cooling assembly, the cooling assembly including a cooling channel: the cooling channel extends from a hole in a first side of the battery module to a hole in a second side of the battery module; and the cooling channel is positioned such that heat generated within the cell housing can be transferred to a cooling fluid, the cooling fluid flowing from the first side of the battery module to the second side of the battery module via the cooling channel, wherein the battery modules are arranged in a stacked structure such that the cooling channels of at least one battery module are aligned with the cooling channels of at least one adjacent battery module, the method including: identifying a battery module to be removed from the stacked configuration; engaging a lifting mechanism with the battery module immediately above the identified battery module; and using the lifting mechanism to lift the battery module above the identified battery module from the stacked structure.

[0040] In another aspect of the present disclosure, a method of manufacturing a battery module stack is provided, including: using a lifting mechanism to position a battery module stack according to any of the above embodiments relative to an interface base in a predetermined position, wherein, in the predetermined position, the cooling channels of the battery module stack are aligned within one or more holes formed in the interface base such that air conveyed through the interface base can flow into the cooling channels of the battery module stack. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Embodiments of the present disclosure will now be described in conjunction with the accompanying drawings, wherein

[0042] Figure 1 a battery module stack according to an embodiment of the present disclosure is shown;

[0043] Figure 2 a top view of a battery module according to an embodiment of the present disclosure is shown;

[0044] Figure 3 shows Figure 2 the bottom of the battery module;

[0045] Figure 4 shows Figure 2 the rear of the battery module, wherein the rear cover is transparently shown;

[0046] Figure 5 a stacking of battery cells is shown;

[0047] Figure 6 is Figure 2 an exploded view of the battery module;

[0048] Figure 7 and Figure 8 more particularly shows an interlocking battery module according to an embodiment of the present disclosure;

[0049] Figures 9 to 11 Views of a module stack base and an interface base according to an embodiment of the present disclosure;

[0050] Figure 12 Shows air being pushed through Figure 1 the module stack;

[0051] Figure 13 Shows a plurality of module stacks and a group controller according to an embodiment of the present disclosure;

[0052] Figure 14 Shows multiple rows of module stacks and a group controller according to an embodiment of the present disclosure;

[0053] Figure 15 Shows a method of assembling a row of module stacks according to an embodiment of the present disclosure;

[0054] Figure 16 Shows a battery pack according to an embodiment of the present disclosure;

[0055] Figure 17 Shows an interface base according to an embodiment of the present disclosure;

[0056] Figure 18 Shows a group controller module according to an embodiment of the present disclosure;

[0057] Figure 19 Shows the group controller;

[0058] Figure 20 and Figure 21 Shows the top and bottom of a battery module according to an embodiment of the present disclosure;

[0059] Figure 22 and Figure 23 Shows Figure 20 and Figure 21 the cooling and exhaust manifolds of the battery module;

[0060] Figure 24A and Figure 24B Respectively show the power pins in their retracted state and extended state according to an embodiment of the present disclosure;

[0061] Figure 25 is Figure 20 and Figure 21 the rear view of the front cover of the battery module;

[0062] Figure 26 is Figure 25 the front view of the front cover of

[0063] Figure 27 ShowsFigure 16 The top of the battery pack;

[0064] Figure 28 shows Figure 16 The bottom of the battery pack;

[0065] Figure 29 shows Figure 16 The cover of the battery pack; and

[0066] Figures 30A - 30D and Figure 31 shows the circuit diagram of the interconnected battery modules. Detailed Description

[0067] The present disclosure seeks to provide improved battery modules and battery packs. Although various embodiments of the present disclosure are described below, the present disclosure is not limited to these embodiments, and variations of these embodiments may well fall within the scope of the present disclosure, which will be limited only by the appended claims.

[0068] The word "a" or "an" when used in conjunction with the terms "comprising" or "including" in the claims and / or the specification may mean "one", but it is also consistent with the meaning of "one or more", "at least one", and "one or more than one", unless the context clearly dictates otherwise. Similarly, the word "another" may mean at least a second or more, unless the context clearly dictates otherwise.

[0069] As used herein, the terms "coupled", "coupling" or "connected" can have several different meanings, depending on the context in which these terms are used. For example, the terms coupling, coupling or connected can have a mechanical or electrical meaning. For example, as used herein, the terms coupling, coupling or connected may indicate that two elements or devices can be directly connected to each other, or can be connected to each other via one or more intermediate elements or devices through electrical elements, electrical signals or mechanical elements, depending on the specific context. When used in association with a list of items, the term "and / or" herein means any one or more of the items in the list.

[0070] As used herein, referring to "about" or "approximately" a number or referring to "substantially" equal to a number means within + / - 10% of that number.

[0071] In the following text, a battery module generally refers to a housing that contains a plurality of interconnected battery cells. The battery cells form one or more battery cell stacks (also referred to as battery cell strings). A plurality of battery modules stacked on top of each other generally form a battery module stack (or simply referred to as a module stack). When one or more battery modules are connected to a module controller (also known as a group controller), the combination of the battery module and the module controller generally forms a battery pack. The group controller can be stacked together with the battery module stack or can be located outside the module stack.

[0072] Turn to Figure 1 , a battery module stack 100 according to an embodiment of the present disclosure is shown. The module stack 100 is formed by a stacked arrangement of different components. Specifically, the module stack 100 includes: a module stack base 10 at its bottom, a stack of interconnected battery modules 50 stacked on top of the module stack base 10, and a module stack cover 80 located at the top of the module stack 100 and directly adjacent to the uppermost battery module 50. The module stack 100 is stacked on top of an interface base 95 such that the module stack base 10 engages with the upper surface of the interface base 95. Those skilled in the art will understand that the present disclosure extends to battery packs having any number of stacked battery modules and having any number of columns of stacked battery modules. Additionally, in some embodiments, the module stack can be formed without the module stack cover 80 and / or without the module stack base 10. Thus, in some embodiments, the module stack can include only one column or multiple columns of stacked battery modules.

[0073] The footprint of the module stack 100 is substantially the same as the footprint of a standard-sized pallet. Specifically, the footprint of the module stack 100 is substantially the same as the standard EUR2 European-sized pallet defined by the European Pallet Association (e.g., 1,200 x 1,000 x 144 mm), but as those skilled in the art will recognize, the present disclosure extends to module stacks having any other suitable footprint dimensions.

[0074] Turn to Figure 2 and Figure 3 , a top view and a bottom view of the battery module 50 are shown. The battery module 50 includes a pair of cell housings 52a, 52b, each housing containing a battery cell stack 72a, 72b ( Figure 2 and Figure 3 not shown in). Cooling fins 53 are provided on the left, right, and lower sides of the cell housings 52a, 52b away from the battery module 50 for facilitating heat transfer from the inside of the cell housings 52a, 52b to the outside of the battery module 50.

[0075] An exhaust assembly is provided at the rear of the battery module 50, and the exhaust assembly includes a pair of exhaust channels 57a, 57b. The exhaust channels 57a, 57b extend from exhaust holes formed in the lower and upper sides of the battery module 50. Thus, the exhaust channels 57a, 57b extend from the lower side of the battery module 50 to the upper side of the battery module 50. The exhaust channels 57a, 57b are used to convey exhaust bodies (e.g., in response to one or more battery cell stacks 72a, 72b undergoing thermal runaway) that may be formed within the unit housings 52a, 52b away from the battery module 50. Specifically, each exhaust channel 57a, 57b is fluidly coupled to the interior of one of the unit housings 52a, 52b such that exhaust discharged from one of the battery cell stacks 72a, 72b within the unit housing can be diverted away from the battery module 50.

[0076] The extension between the unit housings 52a, 52b is a cooling assembly including a cooling channel 56. The cooling channel 56 extends from cooling holes formed in each of the lower and upper sides of the battery module 50. Thus, the cooling channel 56 extends from the lower side of the battery module 50 to the upper side of the battery module 50. The cooling channel 56 is used to convey a cooling fluid between the unit housings 52a, 52b. The cooling channel 56 extends substantially along the entire length of the unit housings 52a, 52b and is separated from the exhaust channels 57a, 57b by a physical interface such that the cooling fluid flowing through the cooling channel 56 does not mix with the exhaust flowing through the exhaust channels 57a, 57b. The cooling fluid may include, for example, a liquid coolant, a forced air flow (e.g., cold air forced up or down through the battery module 50 via the cooling channel 56), or a passive air flow (e.g., air flowing through the battery module 50 by free convection via the cooling channel 56).

[0077] When two or more such battery modules 50 are stacked on top of each other, the cooling channel 56 of one battery module 50 is aligned with the cooling channel 56 of an adjacent battery module 50. Additionally, the exhaust channels 57a, 57b of one battery module 50 are aligned with the exhaust channels 57a, 57b of an adjacent battery module 50.

[0078] In some embodiments, the exhaust channels 57a, 57b and the cooling channel 56 may be located elsewhere on the battery module 50. For example, the cooling channel may be provided along each side of the battery module 50 that faces away from the battery module 50. As another example, the battery module 50 may include a single exhaust channel that serves both unit housings 52a and 52b. Those skilled in the art will recognize that any number of cooling channels and exhaust channels may be included in the battery module 50 if the cooling channels and exhaust channels extend from one side of the battery module 50 through the battery module 50 to another side of the battery module 50, and their numbers may vary according to the needs of those skilled in the art.

[0079] At each corner of the battery module 50, a protruding self-locking member 59 is provided. The protruding self-locking member 59 protrudes upward from the battery module 50 and is configured to engage or mate with a corresponding recessed self-locking member 51 provided in the lower side of another battery module 50. Each recessed self-locking member 51 includes a tapered portion to facilitate engagement with the protruding self-locking member 59 of an adjacent battery module 50. The tapered portion allows for a certain tolerance of misalignment between the battery modules 50, such that the battery modules 50 can more easily "self-align" when engaging with each other.

[0080] At the front of the battery module 50, on each of the upper and lower sides of the battery module, power connectors 83 are respectively provided. The power connectors 83 include a pair of conductive pins and a ground connection. The conductive pins can be retractable, as described in connection with Figure 24A and Figure 24B the power pins 67. Each power connector 83 includes a tapered portion to facilitate engagement with the power connector 83 of an adjacent battery module 50. Thus, the male power connector 83 at the top of the battery module 50 includes a tapered portion to facilitate engagement with the tapered female power connector 83 on the lower side of the upper adjacent battery module 50. The tapered portion allows for a certain tolerance of misalignment between the battery modules 50, such that the battery modules 50 can more easily "self-align" when engaging with each other.

[0081] Combined with the tapered portions on one or both of the male and female power connectors 83, the power connectors 83 can be "active" relative to the unit housings 52a and 52b to provide additional tolerance when the power connectors 83 of the battery module 50 mate with the power connectors 83 of adjacent battery modules.

[0082] Figure 4 The rear of the battery module 50 is shown, where the rear cover is removed to show the rupture diaphragm 64. The rupture diaphragm 64 is configured to open in response to sufficient pressure applied to the rupture diaphragm 64, as would occur in the case of thermal runaway occurring within the unit housings 52a, 52b. When the rupture diaphragm 64 opens, the exhaust can flow out from the interior of the unit housings 52a, 52b and leave the battery module 50 via the exhaust channels 57a, 57b.

[0083] Figure 5 A battery cell stack 72 housed within one of the unit housings 52a, 52b is shown. Each battery cell stack 72 includes a plurality of battery cells, and groups of these battery cells are interconnected by busbars 73.

[0084] Go to Figure 6, a module control board service panel 68 is provided at the front end of the battery module 50. The service panel 68 can be removed to expose the module control board 69. The module control board 69 includes control, communication and power transmission hardware for the battery module 50, and is responsible for monitoring the battery module 50 and ensuring that the battery cells of the battery cell stacks 72a, 72b remain balanced. The connector 73 (which can be a bus bar in some embodiments) interconnects the power connector 83 to the battery cell stacks 72a, 72b contained in the unit housing 52a, 52b. The cover 55 of the unit housing 52a has been removed, showing the battery cell stack 72a contained therein. The connector 73 is configured to connect the battery cell stacks 72a, 72b in series or in parallel so as to configure the voltage and rated current of the battery module 50.

[0085] The module control board 69 also includes a wireless communication module and / or a group controller that enables the battery module 50 to communicate with one or more other battery modules. In some embodiments, other forms of wireless or wired communication may be implemented, such as optical communication using optical ports provided on the upper and lower sides of the battery module 50.

[0086] Figure 7 and Figure 8 A plurality of stacked battery modules 50a, 50b, and 50c are shown. Battery module 50c is stacked on top of battery module 50b, and battery module 50b is stacked on top of battery module 50a. Figure 8 , it is seen that the protruding self-locking members 59a and 59b of the battery modules 50a and 50b are contained within the receiving outer sleeves 61a and 61b, and within the corresponding recessed self-locking members 51b and 51c of the battery modules 50b and 50c. The weight of the upper battery module 50 pressing downward on the lower battery module 50 (which is arranged just below the upper battery module 50) causes the outer sleeve 61 of the lower battery module 50 to translate downward and actuate the clamp 62 located within the recessed self-locking member 51. When actuated, the clamp 62 engages the protruding self-locking member 59 of the next lowest battery module 50. Therefore, in Figure 8 In the exemplary embodiment of , the outer sleeve 61b of the battery module 50b is translated downward by the weight of the battery module 50c to engage with the clamp 62b of the battery module 50b. As a result, the clamp 62b engages with the recessed self-locking member 59a of the battery module 50a, thereby locking the battery module 50b to the battery module 50a. Since the clamp 62c has not been actuated by the outer sleeve 61c, the battery module 50c remains unlocked relative to the battery module 50b until weight is applied to the battery module 50c (such as, another battery module 50 or the module stack cover 80).

[0087] Figure 9 and Figure 10Upper and lower side views of a module stack base 10 engaged with an interface base 95 are respectively shown. The module stack base 10 includes cooling channels 156 formed in the module stack base 10 and positioned to align with the cooling channels 56 of battery modules 50 stacked on top of the module stack base 10. Additionally, the module stack base 10 includes an exhaust channel 157 at its rear end, which is positioned to align with the exhaust channels 57a, 57b of battery modules 50 stacked on top of the module stack base 10. The module stack base 10 further includes holes 111 for docking with a forklift or similar lifting device for transporting the battery module stack 100 as a whole. As described above, the module stack base 10 also includes a protruding self-locking member 159 such that the stacking of battery modules 50 can be locked to the module stack base 10. In some embodiments, the module stack base 10 includes one or more fans for forcing air through the battery module stack 100. In some embodiments, air can be delivered to the battery module stack 100 through a duct system extending beneath the battery module stack 100, as described in further detail below. Further still, in some embodiments, if the heat duty is low enough, air can flow through the battery module stack 100 by free convection.

[0088] An interface base 95, which can form part of a container on which the module stack 100 is mounted, includes an exhaust port 150 on its lower side for exhaust flow to leave the module stack 100. As Figure 11 shown, the interface base 95 also includes a power connector 173 for electrically coupling the module stack 100 to a group controller (not shown).

[0089] Figure 12 Forced air flowing upward through the center of the module stack 100 is shown. Specifically, the forced air is directed through the interface base 95, through the cooling channels 156 of the module stack base 10, and through each cooling channel 56 of the battery modules 50. A stack cover 80 at the top of the module stack 100 enables the topmost battery module to be locked to the next-lowest battery module. Additionally, the stack cover 80 seals the exhaust channels 57a, 57b and the cooling channels 56 of the topmost battery module. Thus, by covering the top of the module stack 100, the air pushed into the module stack 100 is directed out of the sides of the module stack 100 via gaps 81 provided between adjacent stacked battery modules 50. In some embodiments, instead of the stack cover 80, the topmost battery module can include cooling channels 56 and exhaust channels 57a, b that are integrally sealed with the battery module. In other embodiments, the air flowing through the module stack 100 can exit at one or more other locations provided within the module stack 100.

[0090] In some embodiments (not shown), a liquid coolant opposite to or in addition to the airflow may be used to cool the battery module 50. In such an embodiment, each battery module 50 may include one or more cooling plates positioned below the cell housings 52a, 52b. The coolant entering the cooling plates may be distributed across the entire cooling plates (thereby absorbing heat from the cell stacks 72a, 72b) and may then be directed upwardly away from the cooling plates via tubing or similar conduits positioned within the cooling channels 56. After flowing through the cooling channels 56, the coolant may be directed to the cooling plates in the next battery module 50 in the sequence of battery modules 50. In some embodiments, the liquid coolant may flow directly through the cooling channels 56 without the need for tubing. In some embodiments, instead of or in addition to the cooling plates located on the lower side of the battery module 50, the battery module 50 may have one or more cooling plates disposed on one or more other sides of the battery module 50.

[0091] Figure 13 An example of a multi-stack battery pack 1000 including a plurality of module stacks 100a-h is shown. Each module stack 100a-h is positioned adjacent to one or more other module stacks 100a-h. The group controller 160 is located at the end of the plurality of module stacks 100a-h. In some embodiments, the group controller 160 may be located at other positions relative to the plurality of module stacks 100a-h. Additionally, while only a single row of module stacks is shown, those skilled in the art will recognize that the present disclosure extends to multi-stack battery packs having any suitable number of rows.

[0092] Each module stack 100a-h may be communicatively and operably coupled to the group controller 160. Thus, a single group controller is used to interface with all of the module stacks, thereby reducing the number of group controllers required to control the module stacks 100a-h. Cold air may be delivered to each module stack 100a-h via the plenum chamber 170 extending beneath each interface base 95 that engages the module stacks 100a-h. The air may flow along the plenum chamber 170 and may be directed upwardly through the central cooling channel of each module stack 100a-h, the central cooling channel being formed by the cooling channel 156 of the stack base 10, and the adjacent arranged cooling channels 56 of the battery modules 50 form the module stack.

[0093] Figure 14An exemplary embodiment of high-density battery storage is shown having a plurality of rows of battery module stacks 100 arranged side by side. Each row of module stacks 100 terminates at a group controller 160 configured to control the module stacks 100 in the associated column of module stacks 100. The module stacks 100 may be oriented such that the module service panel 68 faces a service aisle that is between every second pair of adjacent rows of module stacks 100. In some embodiments, to reduce the footprint of the plurality of battery packs 100, the rows of module stacks 100 may be positioned directly adjacent to each other without any service aisles. To service the module stacks 100, a lifting mechanism may be used to extract individual modules 50 from the module stacks 100. Another lifting mechanism 98 (such as an I-beam hoist) is used to position the stack 100 to engage an interface base 95.

[0094] Figure 15 An example method of assembling a battery pack is shown. Using a lifting mechanism 96 (such as an overhead crane), a stack 100 of battery modules is positioned on a movable pallet 180. For example, the module stack 100 may be suspended from the lifting mechanism 96 by using a lifting strap wrapped around the module stack 100. The stack 100 is then positioned to engage an interface base 95 using another lifting mechanism 98 (e.g., an I-beam hoist). The interface base 95 provides power, communication, and cooling connections for each module stack 100. Once properly positioned, the module stack 100 may be mechanically constrained relative to the interface base 95 prior to use.

[0095] In the following, alternative embodiments of module stacks, battery packs, and battery modules will be described.

[0096] Turning to Figure 16, showing a battery pack 100' according to an embodiment of the present disclosure. The battery pack 100' is formed by a stacked arrangement of different components. Specifically, the battery pack 100' includes an interface base 10' at its bottom, a group control module 30' stacked on top of the interface base 10', and two adjacent columns of interconnected battery modules 50' stacked on top of the group control module 30'. A battery pack cover 80' is positioned on top of the battery pack 100', directly adjacent to the two topmost battery modules 50'. Each column is formed by an equal number of stacked battery modules 50', where the battery modules 50' in one column have an orientation flipped relative to the battery modules 50' in the other column. Thus, the battery modules 50' in the left column (when facing the front of the battery pack 100') are oriented right-side up, i.e., their cooling plates (described further below) face the interface base 10', while the battery modules 50' in the right column are oriented upside down such that their cooling plates face the battery pack cover 80'. This particular stacking of the battery modules 50' is only one possible way of arranging the battery modules 50' within the battery pack 100', and other examples are described in more detail below. In addition, those skilled in the art will understand that the present disclosure extends to battery packs with any number of stacked battery modules and any number of columns of stacked battery modules. Further, in some embodiments, the columns of battery modules may have different numbers of battery modules, in which case the battery pack cover may be separated and jumper cables or busbars may be used to return the power path.

[0097] Turning to Figure 17 , the interface base 10' is shown in more detail. The interface base 10' includes a pair of cooling channels 12a', 12b' that extend from the front portion 16' of the interface base 10' to the upper side at the rear end 18' of the interface base 10'. Cooling air can be drawn through a vent 11' at the front portion 16' of the interface base 10' to the rear end 18', where the cooling air can be forced upward through cooling holes 13a', 13b' (in some embodiments, air can be drawn into the interface base 10' through one or more other locations). Adjacent cooling holes 13a', 13b' are provided with thermal runaway or exhaust holes 15a', 15b'. The exhaust holes 15a', 15b' are part of exhaust channels 17a', 17b' that communicate with corresponding thermal runaway exhaust ports 19' on either side of the interface base 10' (in some embodiments, the exhaust channels 17a', 17b' can communicate with a duct system on the bottom of the interface base 10'). The exhaust channels 17a', 17b' and the cooling channels 12a', 12b' are separated by a physical interface 14' such that the cooling fluid flowing through the cooling channels 12a', 12b' does not mix with the exhaust flowing through the exhaust channels 17a', 17b'. The interface base 10' also includes a recess 21 that provides space for a power bus.

[0098] Go to Figure 18 , which more particularly shows the group control module (PCM) 30'. The PCM 30' includes exhaust passages 34a', 34b' that extend from holes in the lower side of the PCM 30' to exhaust holes 38a', 38b' formed in the upper side of the rear end 34' of the PCM 30'. Adjacent exhaust holes 38a', 38b' are cooling holes 36a', 36b' that form part of cooling passages 32a', 32b' that extend from the upper side of the PCM 30' to holes in the lower side of the PCM 30'. The exhaust passages 34a', 34b' and the cooling passages 32a', 32b' are separated by a physical interface 31' such that cooling fluid flowing through the cooling passages 32a', 32b' does not mix with the exhaust flowing through the exhaust passages 34a', 34b'. A optical communication port 33', power pins 35' and a power socket 37' are located at the front of the PCM 30'. The PCM 30' includes a compartment accessible by removing a drawer tray 39'. A main control module 40' ( Figure 19 ) is housed within the PCM 30'. The main control module 40' is operably and communicatively coupled to the optical communication port 33', the power pins 35' and the power socket 37'. In some embodiments, instead of using an optical communication port, a wireless communication module or a wired connection may be used for communication between the battery modules 50'.

[0099] Go to Figure 20 and Figure 21 , which more particularly shows a view of the battery module 50'. The battery module 50' includes a cell housing 52' that houses a plurality of battery cells. Each battery cell is encapsulated in a cell carrier, e.g., the cell carrier described in PCT Publication WO 2017 / 181284. Other cell structures that do not employ a cell carrier may be used. Electrical energy from the battery cells may be delivered via a bus bar to a battery terminal connection bolt 71' (see below).

[0100] The battery module 50' further includes a cooling assembly 54', which includes a cooling exhaust manifold 55' having a cooling channel 56' that extends from a cooling hole 51' in the lower side of the battery module 50' to a cooling hole 53' in the upper side of the battery module 50'. In the present embodiment, the cooling assembly 54' further includes a radiator in the form of a cooling plate 58' disposed on the lower side of the battery module 50'. Thus, the cooling hole 51' is directly formed within the cooling plate 58' such that the cooling channel 56' extends from the lower side of the cooling plate 58' to the upper side of the battery module 50'. In some embodiments, the battery module 50' may be provided without the cooling plate 58', in which case the cooling channel 56' extends from the lower side of the cooling exhaust manifold 55' to the upper side of the cooling exhaust manifold 55'. The cooling plate 58' includes a radiator (e.g., a fin arrangement of conductive elements) for assisting in transferring heat away from the cell enclosure 52'. The cooling channel 56' is in fluid communication with the cooling plate 58' such that cooled air can flow through the cooling channel 56' and the cooling plate 58'. The air can then exit the battery module 50' at the front portion 61' of the cooling plate 58'.

[0101] Adjacent cooling channels 56' are exhaust channels 57' that extend from an exhaust hole 59' in the lower side of the battery module 50' to a hole 60' in the upper side of the battery module 50'. In the present embodiment, since the battery module 50' includes the cooling plate 58', the exhaust hole 59' is formed within the cooling plate 58'. The cooling channels 56' and the exhaust channels 57' are separated by a physical interface 62' such that the cooling fluid flowing through the cooling channels 56' does not mix with the exhaust gas flowing through the exhaust channels 57'. When two or more such battery modules 50' are stacked on top of each other, the cooling channels 56' of one battery module 50' are aligned with the cooling channels 56' of an adjacent battery module. Additionally, the exhaust channels 57' of one battery module 50' are aligned with the exhaust channels 57' of an adjacent battery module.

[0102] In an alternative embodiment (not shown), the battery module 50' may be cooled using a liquid coolant that is opposite to or in addition to the air flow. In this embodiment, the cooling channel 56' is in fluid communication with the cooling plate 58'. However, the cooling plate 58' includes a fluid flow path that extends from a fluid inlet between the cooling channel 56' and the cooling plate 58' to a fluid outlet between the cooling plate 58' and the cooling channel 56'. Thus, the liquid coolant can flow into the cooling channel 56' via the cooling hole 51', flow into the cooling plate 58' via the liquid inlet, flow back out of the cooling plate 58' via the liquid outlet, and then flow out of the cooling channel 56' via the cooling hole 53'. The discharged coolant then returns to the bottom of the stack where the discharged coolant can be recycled to the coolant system, e.g., the coolant system of the container on which the battery pack 100' is deployed.

[0103] Therefore, the cooling assembly 54' is positioned such that heat generated within the unit housing 52' can be transferred to a cooling fluid (e.g., a liquid coolant or a gas coolant such as cold air) that flows from the lower side of the battery module 50' to the upper side of the battery module 50' via the cooling channel 56'.

[0104] Figure 22 and 23 The cooling exhaust manifold 55' is shown in more detail. Specifically, the cooling exhaust manifold 55' includes a thermal runaway exhaust port 63' that extends from within the unit housing 52' to the exhaust channel 57' via the cooling channel 56'. A rupture diaphragm 64' is disposed at the interface between the exhaust port 63' and the exhaust channel 57'. The rupture diaphragm 64' is configured to open in response to sufficient pressure applied to the rupture diaphragm 64', as would occur in the case of a thermal runaway within the unit housing 52'.

[0105] Returning to Figure 20 and Figure 21 , at the front end of the battery module 50', an optical communication port 65' is provided on the top side of the battery module 50'. Additionally, a manual power switch 66' is provided on the front face of the battery module 50' and is configured to control the retraction and extension of the power pin 67', as described in further detail below. The main control board service panel 68' can be removed from the front face of the battery module 50' to expose the main control board 69', as visible in Figure 26 . Thus, for example, by providing the main control board 69' including control, communication, and power transmission hardware at the front end of the battery module 50', the servicing of the battery module 50' can be facilitated.

[0106] As described above, instead of using an optical communication port, a wireless communication module or a wired connection can be used for communication between the battery modules 50'. Additionally, in order to service the main control board 69', it may be necessary to first retract the power pin 67' by actuating the manual power switch 66'.

[0107] Figure 24A and Figure 24B show the power pin 67' in the retracted state and the power pin 67' in the extended state, respectively. As visible in Figure 24B , by using, for example, a suitable linear rotary converter, rotation of the manual power switch 66' causes a corresponding linear movement of the power pin 67'. As Figure 25 shows, a power socket 70' is disposed opposite the power pin 67'. A battery terminal connection bolt 71' connects the power pin 67' and the power socket 70' to the terminal of a battery cell 72' housed within the unit housing 52'.

[0108] Moving on to Figure 27 andFigure 28 , which more particularly shows the top of the battery pack 100'. The cover 80' seals the exhaust passage 57' and the cooling passage 56' of the uppermost battery modules 50a', 50b'. In this way, the air drawn into the battery pack 100' is guided out from the front of the battery pack 100' via the front of the cooling plate 58'. In an alternative embodiment, instead of the cover, the uppermost battery modules 50a', 50b' may include a cooling passage 56' and an exhaust passage 57' that are integrally sealed with the battery modules.

[0109] The battery pack 100' further includes a stabilizing mechanism that is designed to provide stability to the battery pack 100' in the absence of a rack, for example to prevent the battery modules 50' from accidentally moving out of their stacked arrangement. In this embodiment, the stabilizing mechanism includes a compression cable 90' that is attached to the PCM 30' at the front of the battery pack 100', extends in a groove 82' formed in the cover 80' above the cover 80', and is attached to the PCM 30' at the rear side (not shown) of the battery pack 100'. A bridging bus bar 95' (which may be a cable in some embodiments) interconnects the power pins on the leftmost top battery module 50a' with the power sockets on the rightmost top battery module 50b'. Figure 28 The compression cable 90' attached to the PCM 30' at the front of the battery pack 100' is shown.

[0110] To remove a battery module 50' from the battery pack 100', retract the power pins 67' of the battery module to be removed and disengage the stabilizing mechanism by removing the compression cable 90'. Then, use a lifting mechanism to remove the battery module located directly above the battery module to be removed. Then the battery module to be removed can be simply removed from the stack, for example for repair. The same method can be used to disassemble the stack of battery modules.

[0111] Turning to Figures 30A to 30D , various exemplary ways in which the battery modules (e.g., battery module 50 or battery module 50' of the battery module stack) of a battery module stack (e.g., battery module stack 100 or the module stack of battery pack 100') can be connected are shown.

[0112] Figure 30A The battery pack 200 is shown, where, similar to Figure 16 the embodiment of, the group controller 202 is integrated with the module stack 204. Specifically, Figure 30A the first left column 206 of battery modules located near the right column 208 of battery modules is shown. The orientation of the battery modules in the right column 208 is flipped relative to the orientation of the battery modules in the left column 206 such that the power connectors on one column are arranged adjacent to the power connectors on the other column, thereby minimizing the circuit path length of the battery module string.

[0113] Figure 30B An exemplary alternative arrangement of a battery module with single-column interconnections is shown. A return conduction path 210 is provided from the cover 212 back to the group controller 202. Figure 30C Another similar arrangement of a battery module with single-column interconnections is shown. However, each battery module includes a stack of two adjacent battery cells (similar to Figure 2 the embodiment of Figure 30D The same arrangement as Figure 30C is shown, except that instead of optical communication ports, a wireless communication transceiver or module 214 is used to enable communication between the battery modules. As described above, hardwired connections may alternatively be used for communication.

[0114] Figure 31 An alternative configuration including a plurality of module stacks 300 and a single group controller 310 (similar to Figure 13 the embodiment of

[0115] In the above embodiments, the cooling fluid may also be used to heat the battery modules. An example scenario is when the battery modules are not in use and the surrounding environment is cold. The "cold" battery modules benefit from being heated to allow them to be used more effectively. "Cold start" is a problem for most battery technologies.

[0116] In addition, in the above embodiments, the battery modules may include one or more self-aligning features for assisting in the alignment of a plurality of battery modules engaging with each other. Specifically, the self-aligning features allow the battery modules to drop onto each other with a certain misalignment tolerance. For example, these recessed self-locking members may include tapered portions, as described above.

[0117] Although the present disclosure has been described in connection with specific embodiments, it should be understood that the present disclosure is not limited to these embodiments, and those skilled in the art may implement changes, modifications, and variations of these embodiments without departing from the scope of the present invention. It is further contemplated that any aspect or any part of any embodiment discussed in this specification may be implemented or combined with any other aspect or any part of any other embodiment discussed in this specification.

Claims

1. A battery module stack, comprising: a plurality of battery modules, each battery module comprising: at least one unit housing for accommodating a plurality of battery cells; and a cooling assembly, the cooling assembly comprising a cooling channel: the cooling channel extends from a hole in a first side of the battery module to a hole in a second side of the battery module; and the cooling channel is positioned such that heat generated within the unit housing can be transferred to a cooling fluid, the cooling fluid flowing from the first side of the battery module to the second side of the battery module via the cooling channel, wherein the battery modules are arranged in a stacked structure such that the cooling channels of at least one battery module are aligned with the cooling channels of at least one adjacent battery module, wherein each battery module further comprises: an exhaust assembly, the exhaust assembly comprising an exhaust channel extending from a hole in a first side of the battery module to a hole in a second side of the battery module; and an exhaust port extending from the unit housing to the exhaust channel; and the exhaust channels of at least one battery module are aligned with the exhaust channels of at least one adjacent battery module, wherein the cooling channel and the exhaust channel are separated by a physical interface such that the cooling fluid flowing through the cooling channel does not mix with the exhaust gas flowing through the exhaust channel.

2. The battery module stack according to claim 1, further comprising: a base at the bottom of the stacked structure; and an air delivery device configured to cause air to flow through the base via the cooling channel and through the cooling channels of the stacked battery modules, the cooling channels being formed within the base and being in fluid communication with the cooling channels of the stacked battery modules.

3. The battery module stack according to claim 2, wherein, the base includes an exhaust outlet in fluid communication with the exhaust channels of the stacked battery modules.

4. The battery module stack according to claim 1, further comprising: a set of controllers communicatively coupled to the battery modules and operable to control the operation of the battery modules.

5. The battery module stack according to claim 4, wherein, the set of controllers is stacked with the battery modules.

6. The battery module stack according to claim 1, further comprising: a cover positioned at the top of the stacked structure such that the cooling channels of the topmost battery module of the stacked structure are sealed.

7. The battery module stack according to claim 1, further comprising: a stabilizing mechanism configured to apply a compressive force to the stacked structure to stabilize the stacked structure.

8. The battery module stack according to claim 7, wherein, the battery module stack further includes a cover positioned at the top of the stacked structure such that the cooling channels of the topmost battery module of the stacked structure are sealed, the stabilizing mechanism includes one or more cables or rods attached to the cover and attached to one or more points at least as low as the bottommost battery module of the stacked structure.

9. The battery module stack according to claim 1, wherein, Each battery module further includes one or more locking members that engage corresponding locking members of one or more of the immediately adjacent upper battery module and the immediately adjacent lower battery module.

10. The battery module stack according to claim 9, wherein, one or more locking members of the battery module are configured to engage the corresponding locking members of the immediately adjacent upper battery module in response to another battery module being stacked on top of the immediately adjacent upper battery module.

11. A method of assembling a battery module stack by stacking a plurality of battery modules to form a stacked structure, wherein, each battery module includes: at least one unit housing for accommodating a plurality of battery cells; and a cooling assembly: the cooling assembly includes cooling channels that extend from holes in a first side of the battery module to holes in a second side of the battery module; and the cooling assembly is positioned such that heat generated within the unit housing can be transferred to a cooling fluid that flows from the first side of the battery module to the second side of the battery module via the cooling channels; and wherein the stacked structure is configured such that the cooling channels of at least one battery module are aligned with the cooling channels of at least one adjacent battery module, wherein each battery module further includes: an exhaust assembly including exhaust channels that extend from holes in a first side of the battery module to holes in a second side of the battery module; and an exhaust port that extends from the unit housing to the exhaust channels; and the exhaust channels of at least one battery module are aligned with the exhaust channels of at least one adjacent battery module, wherein the cooling channels and the exhaust channels are separated by a physical interface such that the cooling fluid flowing through the cooling channels does not mix with the exhaust gas flowing through the exhaust channels.

12. The method according to claim 11, further including: positioning a cover on top of the stacked structure such that the cooling channels of the topmost battery module of the stacked structure are sealed.

13. The method according to claim 12, further including: applying compression to the stacked structure using a stabilizing mechanism to stabilize the stacked structure.

14. A method of using a battery module stack including a plurality of battery modules, each battery module including: at least one unit housing for accommodating a plurality of battery cells; a cooling assembly including cooling channels: the cooling channels extend from holes in a first side of the battery module to holes in a second side of the battery module; and the cooling channels are positioned such that heat generated within the unit housing can be transferred to a cooling fluid that flows from the first side of the battery module to the second side of the battery module via the cooling channels, wherein the battery modules are arranged in a stacked structure such that the cooling channels of at least one battery module are aligned with the cooling channels of at least one adjacent battery module, wherein each battery module further includes: An exhaust assembly, the exhaust assembly including an exhaust passage extending from a hole in a first side of the battery module to a hole in a second side of the battery module; and An exhaust port extending from the unit housing to the exhaust passage; and The exhaust passages of at least one battery module are aligned with the exhaust passages of at least one adjacent battery module, wherein a cooling passage and the exhaust passage are separated by a physical interface such that cooling fluid flowing through the cooling passage does not mix with the exhaust gas flowing through the exhaust passage, The method includes: Identifying a battery module that needs to be removed from the stacked structure; Engaging a lifting mechanism with a battery module immediately above the identified battery module; and Using the lifting mechanism to lift the battery module above the identified battery module from the stacked structure.

15. A method of manufacturing a battery module stack, including: Using a lifting mechanism to position the battery module stack according to any one of claims 1-10 relative to an interface base in a predetermined position, wherein in the predetermined position, the cooling passages of the battery module stack are aligned within one or more holes formed in the interface base such that air conveyed through the interface base can flow into the cooling passages of the battery module stack.

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