GB2584290A

GB2584290A - All weather battery module

Info

Publication number: GB2584290A
Application number: GB1907490.5A
Authority: GB
Inventors: Gupta Sanjay
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-05-28
Filing date: 2019-05-28
Publication date: 2020-12-02
Anticipated expiration: 2039-05-28
Also published as: GB201907490D0; GB2584290B

Abstract

A battery module comprises a base 201, with a plurality of rechargeable batteries 220 and/or two capacitors. The batteries may be connected in series or in parallel. The module is fully immersed in a dielectric liquid, which has a low boiling point. When the liquid comes into contact with hot batteries, bubbles are created in the liquid as it is heated. Ducts created in the module formed by the position of the batteries and by separators (207, fig 1.5). A lid 202 which has cut-outs which match the base is fitted on top of the module. A temperature measuring device (not shown) is fitted to the underside of the lid with circuitry for the charge controller. A number of battery modules may be place in a larger container (fig 2.2). The batteries may be cooled or heated according to the location and time of year. Damaged modules may be changed. A method of repurposing the battery module is also claimed.

Description

Table of Contents

Description- 2

Title of description 2

Technical Field 2

Background information 2

How this invention solves the technical problems, and how it is different 3 The key objectives of the inventions in this disclosure are: 4 Brief about Drawings 4 Detailed description of preferred embodiment, and how it is manufactured 4 BM (200): 4 Example of intended use 10 Claims 11 All weather hybrid battery module (BM) 11 A method of repurposing the battery modules 12 Glossary 13

Title of Abstract 14

Abstract- 14 -ript nem Title el ilescri ption All weather battery module Battery packs used in large electric vehicles e.g. cars, trucks, buses, vans, trains, boats to supply high voltage power to electric motors. This invention relates to large battery pack technology.

Background information

Vehicles use ICEs to power its drive train. For electric vehicles a battery pack is needed to supply large power to electric motors.

Rechargeable batteries e.g. lithium Ion batteries, which are the building blocks of a battery pack, take long time to charge and have very narrow safe operating temperature and charging temperature range, depending upon its chemistry. In real world electric cars, trucks, buses, vans, trains, boats or backup power unit for hospitals, data centres and industrial units, have to operate in extreme ambient temperature range. Ambient temperatures also put thermal stresses on the batteries during usage and even when the batteries are not being used.

A Lithium ion battery can store only small amount of energy and lots of batteries are electrically connected in series and parallel to store large amount of energy e.g. 100-500KW of energy, which can be used to power large commercial vehicles. Batteries are typically packed into small modules, so that it is easier to assemble a large battery pack and easier to replace a failed module. A number of modules are then installed inside a battery pack.

Batteries can store lots of energy but very slow in delivering this energy -power density of the batteries is very low. Capacitors though store less energy charge and discharge much faster, and have high power density. Hence a hybrid of batteries and capacitors can give a good balance of energy and power.

Capacitors can be safely operated in extreme weather conditions e.g. -40 degree Celsius to 60 degree Celsius. Batteries can safely be operated in much smaller range, depending upon the chemistry.

Thermal mar igerrient: Air Cooling -Simple battery packs/modules deploy air cooling, which uses gaps between the batteries, to circulate the air to cool the batteries during operations and charging.

Benefits of air-cooling: 1. It's cheaper to install, as no pumps are required. Drawbacks of air-cooling - 1. this limits their usage under ambient temperatures outside the normal range, 2. this limits the energy density (energy density for a given cubic metre space) that can be achieved.

3. In the event of small flooding, it can lead to short circuit and permanent damage to the battery pack and associated electronics.

4. Typically the batteries are hard wired. In the event of an accident the fire rescue team has to isolate the battery from rest of the vehicle to safely rescue the occupants.

Cooling Tubes/leaves -Sophisticated battery packs/modules use cooling tubes, which are in direct contact with the battery's sides to cool and heat the batteries. High pressure pumps push cooling/heating liquid through very narrow tubes/leaves interleaved with the batteries, to maximise the energy density and maximise the surface contact area with the batteries. The energy required to cool/heat the battery pack increases as the ambient temp moves away from the safe operating temp of the batteries.

Benefits of the cooling tubes: 1. This provides the higher energy density compared to the air-cooled battery packs.

2. The pack can be used in wider ambient range compared to air-cooled battery packs.

3. The pumps consume small enough energy (compared to the stored energy in the battery pack) to push the cooling/heating liquid around the pack, during the normal ambient temperatures and normal usage of the battery pack.

Drawbacks of cooling tubes: 1. In extreme (temperature below zero and temperatures above 40° C) ambient temperatures, high pressure pumps have to push large amount of the cold or hot liquid through narrow tubes/leaves, and consume a significant amount of energy (compared to the stored energy) to cool/heat the battery pack.

2. There is a an uneven cooling or heating of the pack, as batteries close to the inlet are better cooled or heated, vs. the ones close to the outlet.

3. If one or more of the batteries in the battery pack, get into thermal runaway (uncontrolled heating) which can also lead to fire in the battery pack; it's very difficult to cool the individual batteries and extinguish the fire. Secondary technologies e.g. fuses are deployed to stop the thermal runaway. A separate technology is needed to stop the fire.

4. In the event of small flooding, it can lead to short circuit and permanent damage to the battery pack and the associated electronics.

5. Typically the batteries are hard wired within the battery pack as high power switches produce a lot of heat in close proximity of the batteries. In the event of an accident the fire rescue team has to electrically isolate the battery from rest of the vehicle, to safely rescue the occupants.

:ii i% this hhiendon vv:.1 the tech:a:cal proNems; aihi. hew -et..-.A ditterimt This invention solves the current technical problems through many innovative steps: 1. Thermal management-This innovation uses dielectric liquid with a low boiling point as a carrier of heat from individual batteries/capacitors and the associated electronics in the BTBT to the condenser. Batteries are packed inside battery modules (BMs) and the BMs are laid horizontally and stacked veil-if-nil,/ incida rho 1"1"1-°n, pack. The dielectric liquid which is two phase (liquid-vapour) comes in direct contact with the batteries, the connectors, and the associated electronics. This invention has created vertical ducts in between the batteries. Bubbles are created when subcooled liquid comes in contact with the hot batteries. The bubbles are then channelled into the vertical ducts; these bubbles produce vertical flow of 2 phase dielectric liquid and vapours inside the ducts. These ducts act as heat exchangers. The process of subcooled flow boiling process cools the batteries. This vertical flow also creates low pressure inside the ducts and this creates localised a horizontal movement of liquid, cooling from its tabs.

2. Charging and discharging of batteries in extreme temperatures -this innovation uses capacitors to store energy, which is used to heat the dielectric liquid in the extremely cold temperatures e.g. -40 degree Celsius. From -40 degree Celsius to zero degree Celsius, it's not possible to charge or discharge the lithium ion batteries without damaging its life, capacitors heat up the dielectric liquid to bring the batteries temperature to the safe operating temperature. In extremely hot temperature of 45-60 degree Celsius, especially the tarmac temperature, capacitors supply power to the pump to circulate refrigerant/water through the condenser to cool the battery pack.

3. Modular design -This innovation allows the easy repair and replacement of failed BMs; and allows the extension and reduction of the capacity of the battery pack.

The key obiective:'; of the inventions in tbk dkelosnre are: 1. can be operated (charging and discharging) in temperature range from minus 40°C to over 65°C; 2. high BM energy density (Watt Hr/Kg); 3. minimum power consumption of external pumps and the amount of external liquid/refrigerant needed to be cooled/heated and circulated through the battery pack; 4. the BM is safe in the event of thermal runaway of individual batteries inside the BM and also protection from fire; 5. make the BM highly reliable; and one the key metric of reliability is the expected life of the BM; 6. failed BMs can be repaired or replaced with new BMs; 7. make the batteries last higher number of charge cycles.

Pout Drawings * Figure 1.1 to 1.12 -show the details of the battery module BM(200) * Figure 2.2 -shows the BMs inside the battery pack(100) Detailed description of preferred embodiment, and how itis manure:au ed The inventions will be explained through preferred examples of BM (200).

The aim of battery module BM(200) invention is to design an apparatus of a battery module, which: a. is modular and fit anywhere in the battery pack; b. can be easily manufactured and maintained; c. is highly efficient in cooling the batteries and capacitors, in hot and extremely hot ambient temperatures; d. is also highly efficient in heating the batteries and capacitors, in cold and extremely cold ambient temperatures; e. power consumption in cooling/heating the batteries/capacitors is minimal; f. can be connected in series with other BMs to increase the voltage of the battery pack; g. can be connected in parallel with other BMs to increase the current capacity of the battery pack; h. can be taken out of the series circuit if one or more batteries inside the BM are weakened or failed; i. can be repurposed at end of life in an electric vehicle.

Figure 1.1 is an illustration of a particular version of a BM. In this particular embodiment BM is shown with a base (201) with 62 cylindrical lithium-ion (Li-ion) rechargeable batteries (220) and 2 capacitors. In another embodiment these rechargeable batteries (220) could be nickel-cadmium (NiCd), nickel metal hydride (NiMH) or Lithium Cobalt-oxide LiCoO2 or Lithium Manganese-oxide LiMn2 04 or Lithium Nickel-oxide LiNiO2 or Lithium (NCM) Nickel Cobalt Manganese -Li(NiCoMn)02, Lithium (NCA) Nickel Cobalt Aluminium -Li(NiCoAI)02 or any other chemistry; in the shape of cylinder, tower, pouch or prismatic or any other shape. Further the batteries could be of high energy density. In this disclosure all these rechargeable batteries (220) of different chemistries and shapes are referred to as Batteries (220) in plural and Battery in singular. In this particular embodiment BM has 2 Electric double layer capacitors (EDLC) cylindrical capacitors, also called supercapacitors. In another embodiment these capacitors could be Asymmetric Electrochemical Double Layer Capacitor (AEDLC), Lithium Ion capacitors, or graphene supercapacitors. In this disclosure all capacitors of different electrochemical, chemistries and shapes are referred to as capacitors in plural and capacitor in singular. In another embodiment there could be any number of batteries (220) and any number of capacitors (220) in a BM.

In this disclosure, the combination of batteries and capacitors is optional. The BM(200) can be created just with batteries. The BM(200) can also be created just with capacitors.

The BM (200) is fully immersed in 2 phase dielectric liquid. In this disclosure, the dielectric liquid is a thermally conductive but electrically insulative liquid. E.g. flurocarbons. In this particular embodiment the dielectric liquid chosen is of low boiling point which is lower than the maximum operating temperature of the batteries (220) or capacitors (220), which when comes in contact with hot batteries/capacitors (220) produces bubbles and the dielectric liquid is also heated by convection. In another embodiment a combination of pressure inside the battery pack (101) and the high boiling point of the dielectric liquid can be used, to achieve a higher boiling point of the dielectric liquid inside the battery pack (101). E.g. if the battery pack is used at high altitudes, it would lower the boiling point of the dielectric liquid, the battery pack (101) can then be pressurised to increase the boiling point of the dielectric liquid inside the battery pack (101).

In figure 1.2, in this particular embodiment the BM(200) is shown with cylindrical batteries (220) and capacitors (220), and a separator (207) is arranged between two neighbouring batteries/capacitors (220). In this embodiment, the separator has cross-section of a concave. In another embodiment this separator can have cross section of a rectangle e.g. a separator between two prismatic batteries; or a polygon e.g. a separator between two pouch batteries. One of the innovations here is that separators (207) not only acts as a buttress to keep the battery/capacitor in its place, but also the combinations of these separators and the sides of the batteries/capacitors are used to create vertical ducts (205). Figure 1.2 shows the bottom side of the base (201), it shows a polygon shaped opening in the base and this matches with the duct created between 4 batteries/capacitors. In this embodiment, the polygon shaped duct (205) has 8 sides, with 4 sides created by separators and 4 sides created by the sides of the batteries/capacitors.

In figure 1.2, in this particular embodiment the base (201) also has circular openings for batteries, so that cylindrical batteries/capacitors (220) can slip fit into the openings.

In this embodiment, battery pack(100) has electrical configuration of 128P64P, the BM(200) has 62 batteries (220) electrically connected in parallel and 2 capacitors (220) electrically connected in parallel. However in another embodiment it can be mix of electrically serially and parallel connected batteries/capacitors (220). In further embodiment it could just be batteries in the BM(200) connected in series or parallel. In another embodiment it could just be capacitors in the BM(200) connected in series or parallel.

In figure 1.3, in this particular embodiment, the lid (202) is shown with its outer face and its inner face, which has the mechanical matching openings as the base (201). There is a mechanical mating cut-out for the separator (207) and the cut outs (208), which allow the lid to fit into the base.

In figure 1.4 and 1.5, the lid (202) fits into the base (201). The separators (206) on the edges of the BM mate into the lid. The separators (207) away from the edges, pass through the lid and help align the mechanical openings of the lid with the base.

In figure 1.6 in this particular embodiment, the electrically positive connecting plate (203) is shown, which has the cut-outs matching with base (201) and the lid (202) for the ducts (205), and has openings to electrically connect the positive terminals of the batteries/capacitors (220). In this embodiment positive plate (203) is a PCB with ICs(integrated circuits) and electronic circuits for Battery/capacitor charge controller, temperature measuring devices fitted on the inner side (not shown). There is also an 12C or SMBus or PMbus terminal (212). In another embodiment the negative plate (204) could be the PCB with the Battery/capacitor charge controller, temperature measuring devices, and circuitry, with 12C or SMBus or PM bus terminals (212). In another embodiment the electronic circuitry can be split between positive plate (203) and negative plates (204), hence both plates may have electronic circuitry, and one of them can have 12C or SMBus or PMbus terminals.

In figure 1.6 in this particular embodiment, the positive plate (203) has positive terminal to supply the power from the batteries/capacitors (220) in the BM. In this embodiment of battery pack of 128564P configuration, BM(200) has 62 batteries are electrically connected in parallel with 3.4 nominal voltage of each battery and 4.2v of max voltage of each battery, and two capacitors of 500 Farad with 2.7v of max voltage are also cnnnprtpri to the PCR nlate. The high voltage of the BM in this embodiment is roughly 4.2V. In another embodiment with a battery pack configuration of 1605256P, BM(200) has 248 batteries of 3.4v nominal and 4.2V can be connected in parallel and 8 capacitors of 500 Farad also connected in parallel. In another embodiment large individual batteries may be used e.g. in case of pouch battery. In this disclosure output power terminals (221) of the BM, as shown if figure 1.6 and 1.8, are referred to as module high voltages (HV) terminals.

As shown in figure 1.6 and 1.7, in this particular embodiment, the positive plate (203) has positive HV terminal (221) to supply power to the battery pack's (100) sidewall mounted HV terminal (132); and also has positive charging terminal (211) to receive power from the battery pack's (100) sidewall mounted charging terminals (142). Battery/capacitor charge controller 240 (not shown) gets power from this charging terminal (211) to charge the batteries. This charging voltage can be any voltage from 12v to 48v. In another embodiment the charging voltage could be higher voltage e.g. 90v. In this disclosure all module charging voltage terminals (211) are referred to as module charging terminals.

In figure 1.7 in this particular embodiment, the positive plate (203), and the negative plate (204) are shown. The negative plate (204) also has the mechanical cut-outs matching with base (201), the lid (202), and the ducts (205), and has openings to electrically connect the negative terminals of the batteries. The negative plate (204) has negative module HV terminal (221) and negative module charging terminal (211).

As shown in figure 1.8, in this particular embodiment, the base (201) with batteries/capacitors (220), the lid (202), the positive plate (203) and the negative plate (204) are assembled to form a BM (200). It has the separators (207) extending vertically from the BM, which are designed to mate with another BM (200) which is stacked on top. There are matching openings in the base (201), as shown in figure 1.2, which mate with the separators (207) of the BM (200) stacked below.

Figure 1.8 shows the complete BM (200), in the particular embodiment of battery pack (100), it has 128 such BMs. These BMs are not location specific and can be located anywhere within the battery pack (100). There are standardised 4 electrical terminals, 2 module HV (positive and negative) terminals (221), and 2 module Charging (positive and negative) terminals (211); and 2 electronic communication (l2C or SMBus or PMbus) terminals (212) per BM. This eases the manufacturing and maintenance of the BMs. This modular design of BM (200) is another innovation e.g. in this embodiment each BM has identical electrical configuration of 64P. In another embodiment of BM in a battery pack configuration of 1605256P, there are 80 BMs; each BM with 2S256P ( 2 sets of 256 parallel connected batteries/capacitors) configuration. In preferred embodiment, the configuration of 160S256P is implemented in 640 BMs; each BM is 64P (62 batteries and 2 capacitors). In another embodiment of the BM the communication terminals (212) can be also be missed altogether and implemented using wireless connections. In another embodiment capacitors can be missed altogether e.g. with improved technology in batteries e.g. graphene batteries.

As shown in figure 1.9, ducts (205) go through the negative plate (204), the base (201), the lid (202) and the positive plate (203).

Figure 1.10 shows when BMs (200) are stacked vertically, the ducts (205) within each BM (200) align and form straight through vertical ducts (205).

Figure 1.8 and figure 1.11 show the fully assembled BM(200). It has two module (positive and negative) charging terminals (211), two module HV terminals (221), and two communication terminals (243). The figures 1.8 and 1.11 also show how the base (201), the lid (202), the positive plate (203) and the negative plate (204) come together to form the BM(200). The figures also show the separators (207), stick out of the BM which mate with another BM (200) stacked on top. The figures 1.8 and 1.11 also show how the batteries (220) and the ducts (205) are symmetrically arranged.

How rik,.se ducts work o hear exchokyers to E3._.-. es; When the dielectric liquid in the duct comes in contact with the hot batteries/capacitors (220), portion of the liquid is converted into bubbles resulting in mixture of bubbles and liquid. In this embodiment as shown in figure 1.9, the separators (207), guide the bubbles into the duct (205). As shown in figure 1.12, these bubbles create a vertical flow (251) of bubbles and dielectric liquid inside the ducts (205), prior to boiling of the dielectric liquid. This results in cooling of the battery/capacitor sides by convection. Bubbles and the liquid reach the surface of the liquid (as the BM is submerged and the surface of the liquid is outside the BM) and some of the bubbles detach from the liquid and are cooled by the condenser. The battery pack delivers the subcooled liquid at the base of the BM. Each battery/capacitor (220) side is cooled by 4 ducts (205). As the width of the duct is large compared to the size of the bubbles the core of the duct stays in liquid state, the vertical flow (251) of liquid continues for long time, under normal usage of the battery and in the normal ambient temperatures. However if the temperature rises in the core of the duct either due to continued heavy use of the batteries/capacitors or in extreme ambient temperatures, more vapours are generated in the duct as liquid boils on the surface of the batteries/capacitors, bubbly flow will increase the vertical lift and reduced pressure inside the duct will suck in more subcooled liquid from the base of the BM. This results in faster circular flow of the liquid until the temperature falls below the boiling point. Battery pack controller (140) controls the flowrate of coolant in the condenser. Thus the ducts (205) act as heat exchangers with sides of the batteries/capacitors (220) are cooled by the subcooled liquid which enters at the bottom of the BM and liquid and bubbles leave at the top of the BM.

In this disclosure temperatures below zero and temperatures above 40° Celsius are referred to extreme temperatures and temperature between zero and 40° Celsius are referred to as normal temperatures.

This is another key innovation here that the subcooled liquid is serviced at the bottom of the ducts (205) and cooling of the batteries/capacitors (220) is achieved using the process known as 'Subcooled flow boiling' of dielectric liquid, this allows the BMs to operate further away from Critical heat flux conditions (thermal limit where suddenly heat transfer efficiency decreases and creates a overheating).

(There are two types of boiling phenomenon -pool boiling and flow boiling. In pool boiling the heating surface is submerged in the liquid whereas flow boiling is normally confined to flow channels. Subcooled flow boiling in this disclosure is referred to as boiling when the flow temperature is below the saturation level).

Even if a single duct gets into saturated state and vapour percentage reaches close to 100% e.g. a single battery overheats due to its chemistry etc, the BM which is made of material with very high thermal conductivity and preferably also a microporus material, redistributes the heat away from the duct and the duct will quickly go back to the liquid state. As each battery/capacitor is cooled by 4 ducts (205), a saturation state in a single duct does not severely impact the battery, as the battery/capacitor will continue to be cooled by other 3 ducts (205) and from the tab. These are further innovations here, the heat conducting material of the BM is used to create second line of defence, to act as a heat distributor should a single duct gets into saturated state; and redundancy is created for each battery in terms of exposure to ducts (205) i.e. in this embodiment each battery is part of 4 ducts (205).

The battery/capacitor sides which are exposed to ducts (205) can be optionally coated with microporous material to enhance the heat transfer from the sides e.g. if very high current 4C or more is drawn from the batteries e.g. in the case of performance electric vehicles.

Even if a single battery goes into thermal runaway and fire during charging or discharging, the subcooled liquid in all four ducts (205) will put out the fire, the ducts will act as chimneys to let the fumes escape the BM, and the battery pack controller (140) will open the solenoid valve (113) to release the fumes and smoke. The separators also act as barriers to shockwave or cascade effect of thermal runaway or explosion.

The battery pack controller (140) checks the temperature of the BMs continuously, and if the temperature within BMs reaches beyond its tolerance range, it switches off the circuit using the relays, to protect the BM (200) and the battery pack. This is another innovation here -the battery pack controller (140) acts as third line of defence and battery pack controller does not need to severely restrict the usage of the battery pack, as isolated event of an individual battery heating is handled by the BM (200).

In this embodiment the battery pack controller is installed inside the battery pack, however in another embodiment it can be installed outside the battery pack(100).

sgac 01 BM( 2;j0? .6:Men, pack (100q Figure 1.12 shows, when the BMs (200) are vertically stacked, the ducts (205) of all the vertical stacked BMs (200) are aligned to form vertical ducts (205). The separators (207) of each BM (200) are used to vertically align the BMs (200).

The vertical flow continues through the stacked BM (200), inside the ducts (205), until it reaches the surface of the dielectric liquid. As shown in figure 1.12, the vertical flow (251) of dielectric liquid also creates a low pressure inside the ducts (205); and low pressure creates a localised horizontal flow (250) of liquid towards the ducts; and the low pressure sucks in hot liquid from the gaps in between the stacked BM (200), which in turn sucks in hot liquid from the tabs of the batteries; harnessing the effects documented in Bernoulli's theorem.

Excel: Me uttiutended use * A unit of energy for large electric vehicles e.g. trucks, SUVs, vans, trains * Backup power unit for hospitals, data centres and industrial units * Energy storage unit for solar panels

Claims

bybdei battery §31.0thde (BM) 1. Battery module (BM) is an apparatus, a module to hold plurality of rechargeable batteries/capacitors, comprises: a. the said batteries/capacitors are electrically arranged in one or more groups where each group of batteries are electrically connected in a parallel or in series with the other group; b. the said BM is constructed in such a way that all the vertical openings at the top and at the bottom plates of a BM are mechanically matched, to form vertical ducts using sides of the batteries as walls of the ducts; c. the said BM and the said batteries/capacitors are fully submerged in a 2 phase (liquid and vapour) dielectric liquid; d. the bubbles of 2 phase liquid heated by the sides of the batteries/capacitors are channelled through the said ducts using mechanical buttresses or separators; e. the bubbles create vertical flow of said dielectric liquid and bubbles inside the said ducts; f. subcooled dielectric liquid enters the duct through the bottom plate and hot liquid leaves the duct through the top plate; g. the said ducts work as heat exchangers; h. the process known as Subcooled flow boiling' transfers the heat from the sides of the batteries/capacitors forming the ducts to the 2 phase dielectric liquid.
2. The BM of claim 1 can be horizontally laid and/or vertically stacked.
3. The BM of claim 1, the said vertical flow of dielectric liquid also creates a low pressure inside the said ducts, and said low pressure creates a localised horizontal flow of liquid towards the ducts; and as the vertical flow leaves the BM the low pressure sucks in hot liquid from the tabs of the batteries/capacitors, harnessing the effects documented in Bernoulli's theorem.
4. The BM of claim 1, consists of the said batteries/capacitors which are preferably coated with microporous material/s.
S. The BM of claim 1, each battery is preferably connected to the electrically conducting lid through a thermal runaway fuse, further preferably connected to the PCB lid through a PCB mounted thermal runaway protection device/ resettable fuse.
6. The BM of claim 1, comprises openings in the said lid and mechanically matching openings in the base of the said BM; and as long as ducts can be created by mechanically matching lid and base openings, the shape and the size of openings in the lid or the base or both can be changed e.g. the size of the openings can be increased with a reduction in the energy density of the said BM or can be decreased with a limitation on the range of the temperatures the BM can be used for.
7. The BM of claim 1, preferably comprises of surface cooling/heating as well as tab cooling/heating of the said batteries/capacitors, when vertically stacked.
8. The BM of claim 1, the said buttresses or separators, can be of any shape and thickness.
9. The BM of claim 1, the said buttresses or separators, preferably extend out from a side of the said BM and these extended buttresses allow the stacking and mating with the other BMs; such that the said ducts of stacked BMs form a continuous vertical duct.
10. The BM of claim 1, consists of said capacitors power the heaters which heat the dielectric liquid, and the dielectric liquid in turn heat the batteries in extreme weather.
11. the BM of claim 1, preferably also consists of heating of the batteries/capacitors, when bubbles produced by a heating source below the said BM/s are channelled through the said ducts, the heated dielectric liquid enters the ducts from the bottom plate and cold dielectric liquid leaves ducts from the top plate, and dielectric liquid heats the sides of the batteries/capacitors by convection, thus the ducts work as a heat exchanger by transferring the heat from the dielectric liquid to the cold batteries/capacitors.
12. The BM of claim 1, preferably also consists of the said batteries/capacitors which are preferably arranged such a way inside the said BM that the said bubbles created from one battery/capacitor do not coalesce with the bubbles created from the neighbouring batteries/capacitors.
13. The BM of claim 1, preferably consists of one or more temperature sensors, installed anywhere inside the case.
14. The BM is claim 1 is mechanically modular and the electrical circuitry is also modular so that it can be replaced with another said BM during repair; and more of said BM/s can be joined together to extend the max voltage or max current capacity of a battery pack.
15. The BM of claim 1 is preferably made with electrically insulative but thermally conductive material e.g. Aluminium Nitride, Silicon Nitride etc
16. The BM of claim 1, preferably consists of battery charge controllers having one or more PCB mounted ICs (integrated circuits) that charge the batteries/capacitors of the said BM.
17. The BM of claim 1 preferably also consists of energy discharging split circuit that switches the source of the BM output current between: i. batteries current only; ii. capacitors current only; in. an optimal mix of batteries and capacitors current;
18. The BM of claim 1 preferably consists of positive and negative module charging terminals.
19. The BM of claim 1 preferably also consists of communication terminals, these are preferably I2C or SMBus or PMbus terminals.
20. The BM of claim 1 preferably also consists of positive and negative module HV terminals.
21. The BM of claim 1 also consists of subcooled dielectric liquid in ducts acts as a fire extinguisher in the event of a fire of one or more batteries or capacitors inside the BM.
22. The BM of claim 1 also consists of ducts act as chimneys to let the gases/fumes escape the BM in the event of fire of one or more batteries or capacitors inside the BM.
23. The BM of claim 1 also consists of separators act as a barrier to shockwave or cascade effect of thermal runaway, in the event one or more batteries or capacitors have thermal runaway or explosion, inside the BM.
24. The BM of claim 1 also consists of if one or more ducts get into saturated state e.g. due to thermal runaway, the BM which is made of material with very high thermal conductivity and preferably also a microporus material, redistributes the heat away from the duct.A An:the:A etrposi'ng the batter? moduks
25. A method of repurposing the battery modules(BM) of claim 1, comprising: a. matching the mechanical fittings of the BMs and the battery pack; b. placing all the BMs inside a larger or smaller battery pack; c. electrically connecting in series or parallel the said BMs inside the battery pack for the desired voltage and current requirements; d. and replacing the failed or weak BMs with new BMs.Glossa ry Dielectric liquid -is a dielectric material (thermally conductive but electrically insulative) in a liquid state. E.g. fluorocarbons Multi layer faced/sided PCB -printed circuit board with multi layers