Systems, devices, and methods for providing heat to electrochemical cells and electrochemical cell stacks

Abstract

Embodiments described herein relate to an electrochemical cell having a heating element integrated into the electrochemical cell. In some aspects, an electrochemical cell includes: an anode current collector; an anode material disposed on the anode current collector; a cathode current collector; a cathode material disposed on a first side of the cathode current collector; a separator disposed between the anode material and the cathode material; and a heating element disposed on a second side of the cathode current collector, the second side being opposite the first side. The heating element may include an electrically conductive material and a conductive material disposed in an insulating material.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 394,341, filed on August 2, 2022, entitled “Electrochemical Cells and Electrochemical Cell Stacks with Series Connections and Methods of Producing, Operating, and Monitoring the Same”; the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] Embodiments described herein relate to electrochemical cells and electrochemical cell stacks that include heating elements and methods of operating and monitoring the same. Background Art

[0004] Lithium-ion cells exhibit difficulty in charging at low temperatures. In fact, it may become unsafe to charge lithium-ion cells at certain low temperatures. The temperature at which it becomes unsafe to charge a cell depends on the chemistry and material design of the cell. When a lithium-ion cell is charged in a cold environment, the ions in the electrolyte are deposited on the surface of the active material in the form of metal due to the reduced ability of the active material to absorb ions. Lithium metal is highly reactive, and the risk of ion deposition on the surface of the active lithium material increases every time a charging current flows through the cell. Over time, lithium metal can form dendrites (e.g., metal columns) that can grow into and through the diaphragm, causing the cell to enter thermal runaway, even when the cell is at a low temperature and a low state of charge (SOC). Electrochemical cells have traditionally been heated via water or pads to distribute heat throughout the cell or cell stack. However, this approach increases the cost of the system and adds extra-process steps, thereby increasing assembly complexity. Therefore, there is a need for an alternative solution for heating electrochemical cells that can enable charging of cells at low temperatures. Summary of the invention

[0005] Embodiments described herein relate to electrochemical cells including heating elements and methods of operating and monitoring the same. In some aspects, an electrochemical cell includes: an anode current collector; an anode material disposed on the anode current collector; a cathode current collector; a cathode material disposed on a first side of the cathode current collector; a separator disposed between the anode material and the anode material; and a heating element disposed on a second side of the cathode current collector, the second side being opposite to the first side. In some embodiments, the heating element may include a conductive material. In some embodiments, the heating element may include a conductive material and an insulating material. In some aspects, an electrochemical cell comprises: a first current collector; a first electrode material disposed on a first side of the current collector; a second current collector; a second electrode material disposed on the second current collector; a separator disposed between the first electrode material and the second electrode material; an insulating layer disposed on a second side of the first current collector, the second side being opposite to the first side; and a metal sheet disposed on the insulating layer and electrically coupled in series with the first current collector, the metal sheet comprising a groove for dissipation of heat. In some aspects, an electrochemical cell comprises: a first current collector; a first electrode material disposed on a first side of the current collector; a second current collector; a second electrode material disposed on the second current collector; a separator disposed between the first electrode material and the second electrode material; an insulating layer disposed on a second side of the first current collector, the second side being opposite to the first side; and a metal wire disposed inside the insulating layer along a circuitous path, the metal wire being connected in series with the first current collector. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 is a block diagram of an electrochemical cell including a heating element according to an embodiment.

[0007] Figure 2 is a block diagram of a heating element according to an embodiment.

[0008] Figure 3A An electrochemical cell including a heating element according to an embodiment.

[0009] Figure 3B yes Figure 3A An exploded view of an electrochemical cell.

[0010] Figure 4A An electrochemical cell including a heating element according to an embodiment.

[0011] Figure 4B yes Figure 4A An exploded view of an electrochemical cell.

[0012] Figure 5A An electrochemical cell including a heating element according to an embodiment.

[0013] Figure 5B yes Figure 5A An exploded view of an electrochemical cell.

[0014] Fig. 6A is a circuit diagram of an electrochemical cell stack including a heating element.

[0015] Figure 6B is a circuit diagram of an electrochemical cell having a heating element that generates heat when the electrochemical cell is balanced.

[0016] Figure 7 is a schematic flow chart of a method of heating an electrochemical cell according to an embodiment. DETAILED DESCRIPTION

[0017] Embodiments described herein relate to methods for producing, operating, and monitoring electrochemical cells and electrochemical cell stacks. In particular, embodiments described herein relate to electrochemical cells including heating elements. Many electrochemical cell systems have required bypass current devices to balance and equalize the charge in the system. Traditionally, balancing is performed using small resistors on a protection circuit board (PCB or PCBA) as part of a battery management system (BMS) or by various DC to DC converters that transfer energy from a cell to a cell, from a cell to a module, or from a cell to a secondary energy rail. When electrochemical cells are balanced, heat energy is generated as current flows through the cells. A major problem with current balancing methods is that the heat energy from balancing must be absorbed by the PCBA of the BMS, which creates the need for: (1) adding cooling to the BMS or (2) significantly increasing the size of the BMS. Balancing electrochemical cells in the PCBA also significantly limits the amount of current available to balance the cells, resulting in very small balancing currents for each BMS board and limited total cell capacity. Typically, any balancing current exceeding 100 mA requires special consideration of heat in the BMS board. Therefore, a more efficient mechanism by which heat can be dissipated from an electrochemical cell will improve overall cell performance.

[0018] In order to meet the above challenges, the embodiments described herein relate to electrochemical cells with heating elements integrated into electrochemical cells. In some embodiments, the heating element may include a thin metal sheet including a conductive coating and / or an insulating layer disposed on a current collector in the electrochemical cell. In some embodiments, a groove or cutout may be etched on the thin metal sheet so that the thin metal sheet has a desired impedance. In some embodiments, the heating element may instead include a metal wire disposed in an insulating layer electrically connected to a current collector in an electrochemical cell, the metal wire along a circuitous path to achieve the desired impedance. The heating element may be controlled by an existing BMS system so that no additional components are required at the cell, module, and battery pack levels, thereby reducing system complexity and limiting additional costs. The heating element may provide heat to the electrochemical cell to enable charging at a lower temperature. The heating element may also provide increased thermal mass for dissipating the heat generated by the balancing current, thereby enabling the use of a higher balancing current. The embodiments described herein may allow direct heating of the electrochemical cell or electrochemical cell stack, thereby improving heating efficiency and reducing heat loss to the surrounding environment.

[0019] Control systems for bypassing energy around a module, battery cell, or battery pack (both charging and discharging) can ensure safe operation, prevent overcharging, and allow full formation of each battery cell. Safety systems can monitor temperature, current, and / or voltage to prevent battery cell damage and thermal runaway due to overtemperature, overcharge, or overdischarge.

[0020] The safety system can also be used to activate the heating element upon receipt of an internal or external signal. Activating the heating element can be used to reduce the total energy of the system to a lower state of charge. A lower state of charge can be selected based on many conditions, such as, but not limited to, a vehicle collision or airport transportation mode. In the event of a vehicle collision, activating the heating element is advantageous (even though this may increase the temperature of the system) because it allows the battery system to be fully discharged (i.e., reduce the charge of the battery system) to prevent potential battery fires when transporting or disposing of the vehicle. For airport transportation, it is desirable to reduce the energy of the battery through a mode selection (such as a physical button), or to select from a human-machine interface to allow the battery to be safely discharged to a lower energy level, thereby reducing the energy content of the battery to a safe level, such as <30% SOC. Other target states of charge can be selected based on many factors. The selection of 30% is based on restrictions on air transportation of lithium-ion batteries imposed at the time of this application.

[0021] Embodiments described herein may include algorithms for detecting cell-level faults, internal short circuits, and other fault modes using sensors. Sensing may be used to sense or determine cell voltage, temperature, current, module-level voltage, module-level temperature, module-level current, battery pack-level voltage, battery pack-level temperature, and / or battery pack-level current. Algorithms may then be used to diagnose the functional status of each battery cell in the system. In some cases, sensing may be accomplished via a battery management system (BMS), test system sensing, auxiliary sensing systems, or any combination thereof. Safety systems may include regional temperature (hot spots), fire detection, smoke detection, hydrogen detection, carbon monoxide (CO) detection, carbon dioxide (CO2) detection, volatile organic compound (VOC) detection, and / or other detection methods to ensure that the system is not damaged or to prevent damage to the system, battery, and facility during formation. Safety systems may include fire extinguishing systems for preventing facility damage, active ventilation systems for preventing facility damage and personal injury, and protection systems for providing transmission protection between cells, modules, and / or battery packs in formation.

[0022] In some embodiments, the energy storage system may include a grid or renewable connection for metering the energy of the formation layer system and providing energy to make up for efficiency losses. In some embodiments, the energy storage system with built-in control can monitor the power demand of the entire facility and park to provide demand load, frequency regulation, peak shaving, load balancing and / or other grid stabilization operations. In some embodiments, the energy storage system can serve the formation system and / or other secondary renewable uses, such as charging station power for plug-in hybrid electric vehicles (PHEV), electric vehicles (EV), or any other suitable specific implementation.

[0023] In some embodiments, the electrodes described herein may include conventional solid electrodes. In some embodiments, the solid electrodes may include a binder. In some embodiments, the electrodes described herein may include semi-solid electrodes. The semi-solid electrodes described herein may be made: (i) thicker (e.g., greater than 100 μm to up to 2,000 μm or even greater) due to the reduced tortuosity and higher electronic conductivity of the semi-solid electrodes, (ii) with a higher active material load, and (iii) with a simplified manufacturing process using less equipment. These relatively thick semi-solid electrodes reduce the volume, mass, and cost contribution of inactive components relative to active components, thereby enhancing the commercial appeal of batteries made from semi-solid electrodes. In some embodiments, the semi-solid electrodes described herein are binder-free and / or do not use binders used in conventional battery manufacturing. Instead, the volume of the electrode that is typically occupied by the binder in a conventional electrode is now occupied by: 1) electrolyte, which has the effect of reducing tortuosity and increasing the total salt available for ion diffusion, thereby offsetting the typical salt depletion effect of thick conventional electrodes when used at high rates, 2) active material, which has the effect of increasing the charge capacity of the battery, or 3) conductive additive, which has the effect of increasing the electronic conductivity of the electrode, thereby offsetting the high internal impedance of thick conventional electrodes. The reduced tortuosity and higher electronic conductivity of the semi-solid electrodes described herein produce excellent rate performance and charge capacity of electrochemical cells formed by semi-solid electrodes. Since the semi-solid electrodes described herein can be made much thicker than conventional electrodes, the ratio of active materials (i.e., semi-solid cathodes and / or anodes) to inactive materials (i.e., current collectors and separators) in the battery formed by the electrochemical cell stack including the semi-solid electrodes can be much higher relative to similar batteries formed by the electrochemical cell stack including conventional electrodes. This significantly increases the total charge capacity and energy density of the battery including the semi-solid electrodes described herein.

[0024] In some embodiments, the electrode materials described herein can be flowable semi-solid or condensed liquid compositions. In some embodiments, the electrode materials described herein can be binder-free or substantially binder-free. A flowable semi-solid electrode can include a suspension of an electrochemically active material (anode or cathode particles or microparticles) and an optional electronically conductive material (e.g., carbon) in a non-aqueous liquid electrolyte. In other words, the active electrode particles and the conductive particles are co-suspended in an electrolyte to produce a semi-solid electrode. Examples of cell architectures utilizing semisolid suspensions are described in U.S. Patent Publication No. 2022 / 0238923, filed on January 21, 2022, and entitled “Production of Semi-Solid Electrodes Via Addition of Electrolyte to Mixture of Active Material, Conductive Material, and Electrolyte Solvent” (“the '923 Publication”) and Provisional Patent Application No. 63 / 354,056, filed on June 21, 2022, and entitled “Electrochemical Cells with High-Viscosity Semi-solid Electrodes, and Methods of Making the Same” (“the '056 Application”), the entire disclosures of which are incorporated herein by reference.

[0025] In some embodiments, the electrochemical cells described herein may include components that may have multiple layers and / or may be coated with one or more materials. Examples of electrodes having multiple layers and / or composition gradients may be found in: U.S. Patent Publication No. US2019 / 0363351, filed on May 24, 2019, entitled “High Energy-Density Composition Gradient Electrodes and Methods of Making the Same” (the '351 Publication), the entire disclosure of which is incorporated herein by reference. Examples of electrodes having selectively permeable membranes are described in: U.S. Patent Publication No. US2019 / 0348705, filed on January 8, 2019, entitled “Electrochemical Cells Including Selectively Permeable Membranes, Systems and Methods of Manufacturing the Same” (the “'705 Publication”), the disclosure of which is incorporated herein by reference in its entirety.

[0026] In some embodiments, the power management system described herein may include any of the aspects described in U.S. Patent No. 10,153,651, filed on October 9, 2015 and entitled “Systems and Methods for Battery Charging” (“the '651 patent”), the disclosure of which is incorporated herein by reference in its entirety. In some embodiments, the battery management system described herein may include any of the aspects described in U.S. Patent Publication No. 2022 / 0278427, filed on May 13, 2022 and entitled “Electrochemical Cells Connected in Series in a Single Pouch and Methods of Making the Same” (“the '427 publication”), the disclosure of which is incorporated herein by reference in its entirety.

[0027] As used in this specification, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, the term "member" is intended to mean a single member or a combination of members, and "material" is intended to mean one or more materials or a combination thereof.

[0028] When used in conjunction with "cylindrical," "linear," and / or other geometric relationships, the term "substantially" is intended to convey that the structure so defined is nominally cylindrical, linear, etc. As an example, a portion of a support member described as "substantially linear" is intended to convey that while linearity of the portion is desired, some nonlinearity may occur in the "substantially linear" portion. Such nonlinearity may result from manufacturing tolerances or other practical considerations, such as, for example, pressure or forces applied to the support member. Thus, a geometric structure modified by the term "substantially" includes such geometric properties within a tolerance range of plus or minus 5% of the geometric structure. For example, a "substantially linear" portion is a portion that defines an axis or centerline whose linearity error is within plus or minus 5%.

[0029] As used herein, the terms "group" and "plurality" may refer to multiple features or a single feature having multiple parts. For example, when referring to a group of electrodes, the group of electrodes may be considered to be one electrode having multiple parts, or the group of electrodes may be considered to be multiple different electrodes. In addition, for example, when referring to multiple electrochemical cells, the multiple electrochemical cells may be considered to be multiple different electrochemical cells or to be one electrochemical cell having multiple parts. Thus, a group of parts or multiple parts may include multiple parts that are continuous or discontinuous with each other. Multiple particles or multiple materials may also be made from multiple items that are produced separately and subsequently joined together (e.g., via mixing, adhesives, or any suitable method).

[0030] As used herein, the term "semisolid" refers to a material that is a mixture of a liquid phase and a solid phase, such as, for example, a particle suspension, a slurry, a colloidal suspension, an emulsion, a gel, or a micelle.

[0031] As used herein, the terms "activated carbon network" and "networked carbon" refer to the general qualitative state of an electrode. For example, an electrode having an activated carbon network (or networked carbon) causes the carbon particles within the electrode to present individual particle morphology and arrangement relative to each other, which promotes electrical contact and conductivity between particles and across the thickness and length of the electrode. In contrast, the terms "unactivated carbon network" and "unnetworked carbon" refer to electrodes in which carbon particles exist as individual particle islands or multi-particle aggregate islands, which may not be sufficiently connected to provide sufficient electrical conduction through the electrode.

[0032] As used herein, the terms "energy density" and "volume energy density" refer to the amount of energy (e.g., MJ) stored in an electrochemical cell per unit volume (e.g., L) of materials (such as electrodes, separators, electrolytes, and current collectors) included for the operation of the electrochemical cell. Specifically, the materials used to package the electrochemical cell are excluded from the calculation of volumetric energy density.

[0033] As used herein, the term "high capacity material" or "high capacity anode material" refers to a material with an irreversible capacity greater than 300 mAh / g, which can be incorporated into an electrode to promote the absorption of electroactive species. Examples include tin, tin alloys such as Sn-Fe, tin oxide, silicon, silicon alloys such as Si-Co, silicon oxide, aluminum, aluminum alloys, metal oxides (CoO, FeO, etc.) or titanium oxide.

[0034] As used herein, the term "composite high capacity electrode layer" refers to an electrode layer having both a high capacity material and a traditional anode material (eg, a silicon-graphite layer).

[0035] As used herein, the term "solid high-capacity electrode layer" refers to an electrode layer having a single solid phase high-capacity material, such as sputtered silicon, tin, tin alloys such as Sn-Fe, tin oxide, silicon, silicon alloys such as Si-Co, silicon monoxide, aluminum, aluminum alloys, metal oxides (CoO, FeO, etc.) or titanium oxide.

[0036] Figure 1 1 is a block diagram of an electrochemical cell 100 according to an embodiment. As shown, the electrochemical cell 100 includes: an anode material 110, which is disposed on an anode current collector 120; a cathode material 130, which is disposed on a first side of a cathode current collector 140; a separator 150, which is disposed between the anode material 110 and the cathode material 130; and a heating element 160, which is disposed on a second side of the cathode current collector 140, the second side being opposite to the first side. In some embodiments, the anode material 110 and / or the cathode material 130 may include a semi-solid electrode material, as described above. In some embodiments, the heating element 160 may be disposed on a first side of the anode current collector 120. The heating element 160 may be electrically connected to the cathode current collector 140 and may generate heat for the electrochemical cell 100 when current flows through the electrochemical cell 100. In addition, the heating element 160 may provide increased thermal mass to improve heat dissipation when current passes through the electrochemical cell 100. As shown, the heating element 160 is electrically connected to the cathode current collector 140 and is in close proximity in an electrical circuit to the cathode current collector 140. In some embodiments, the heating element 160 can be electrically connected to the anode current collector 120 and can be in close proximity in an electrical circuit to the anode current collector 120.

[0037] Figure 2A heating element 260 is shown that includes a resistive member 270, a conductive material 268, and an insulating material 265. In some embodiments, the resistive member 270 may be formed of a conductive material. The conductive material may include, for example, copper, aluminum, silver, nickel, gold, or any suitable combination thereof. The resistive member 270 may be formed according to any suitable form factor, including, but not limited to, a sheet or foil of uniform thickness, a sheet or foil of non-uniform thickness, a non-continuous sheet or foil (e.g., with holes or cutouts), a wire, and / or a combination thereof. In some embodiments, the resistive member 270 may be coated with a conductive material 268 on at least one of the first and second sides of the resistive member 270. In some embodiments, the conductive material 268 may be coated on the first side of the insulating material 265. When current passes through the resistive member 270, the conductive material 268 may promote or enhance the heating of the heating element 260. The heating element 260 may include an insulating material 265. In some embodiments, the insulating material 265 may include a small bag surrounding the resistive member 270 or a single layer disposed between the current collector and the resistive member 270. Insulating material 265 may be used to isolate resistive member 270 from electrical components of the battery cell (eg, terminals, electrodes, active materials, electrolyte, etc.).

[0038] FIG. 3A to FIG. 3B is a diagram of an electrochemical cell 300 including a heating element 360 according to an embodiment. Figure 3A A cross-sectional profile view of an electrochemical cell 300 is shown. Figure 3B An exploded view of the components of electrochemical cell 300 is shown. Figure 3A As shown, the electrochemical cell 300 includes: an anode material 310, which is disposed on an anode current collector 320; a cathode material 330, which is disposed on a cathode current collector 340; and a separator 350, which is disposed between the anode material 310 and the cathode material 330. The electrochemical cell 300 further includes: a resistive member 370, which has a conductive material 368 disposed on a first side of the resistive member 370; an insulating material 365, which is disposed between the resistive member 370 and the cathode current collector 340; and a pouch material 380, which is disposed around the electrochemical cell 300. In some embodiments, the anode material 310, the anode current collector 320, the cathode material 330, the cathode current collector 340, and the separator 350 can be as described above with reference to Figure 1 The described anode material 110, anode current collector 120, cathode material 130, cathode current collector 140, and separator 150 are the same or substantially similar. Therefore, certain aspects of the anode material 310, anode current collector 320, cathode material 330, cathode current collector 340, and separator 350 are not described in further detail herein.

[0039] like Figure 3A and Figure 3B As shown, the resistive member 370 can be a sheet or foil of a conductive material including a surface having grooves or channels 372. The conductive material can include, for example, copper, aluminum, silver, nickel, gold, or any suitable combination thereof. The grooves 372 can be etched (ablated, scored, engraved, cut, melted, stamped, embossed, depressed, etc.) into the resistive member 370 in a specific pattern to change the impedance of the resistive member 370, thereby changing the heat generating ability of the resistive member 370 (depending on the amount of current passing through the electrochemical cell 300). Therefore, the grooves 372 are thinned portions of the resistive member 370 compared to the rest of the resistive member 370 (i.e., the non-grooved portion of the resistive member 370).

[0040] The ratio of the thickness of the resistive member 370 in the groove 372 to the thickness of the resistive member 370 in the non-grooved portion may be between about 0.1 and 1. The ratio of the thickness between the groove portion and the non-grooved portion may be at least about 0.10, at least about 0.15, at least about 0.20, at least about 0.25, at least about 0.30, at least about 0.35, at least about 0.40, at least about 0.45, at least about 0.50, at least about 0.55, at least about 0.60, at least about 0.65, at least about 0.70, at least about 0.75, at least about 0.80, at least about 0.85, at least about 0.90, at least about 0.95. In some embodiments, the ratio of the thickness between the groove portion and the non-grooved portion can be no more than about 1, no more than about 0.95, no more than about 0.90, no more than about 0.85, no more than about 0.80, no more than about 0.75, no more than about 0.70, or no more than about 0.65, no more than about 0.60, no more than about 0.55, no more than about 0.50, no more than about 0.45, no more than about 0.40, no more than about 0.35, no more than about 0.30, no more than about 0.25, no more than about 0.20, no more than about 0.15, no more than about 0.15. Combinations of the above thickness ratios of the resistive member 370 are also possible (e.g., at least about 0.25 and no more than about 0.95 or at least about 0.50 and no more than about 0.75), including all values ​​and ranges therebetween.

[0041] The resistance member 370 has a length L R and width W R In some embodiments, L RIt may be at least about 1 cm, at least about 2 cm, at least about 3 cm, at least about 4 cm, at least about 5 cm, at least about 6 cm, at least about 7 cm, at least about 8 cm, at least about 9 cm, at least about 10 cm, at least about 20 cm, at least about 30 cm, at least about 40 cm, at least about 50 cm, at least about 60 cm, at least about 70 cm, at least about 80 cm, or at least about 90 cm. In some embodiments, L R Can be no more than about 1m, no more than about 90cm, no more than about 80cm, no more than about 70cm, no more than about 60cm, no more than about 50cm, no more than about 40cm, no more than about 30cm, no more than about 20cm, no more than about 10cm, no more than about 9cm, no more than about 8cm, no more than about 7cm, no more than about 6cm, no more than about 5cm, no more than about 4cm, no more than about 3cm or no more than about 2cm. The combination of the above lengths is also possible (for example, at least about 1cm and no more than about 1m or at least about 3cm and no more than about 10cm), including all values ​​and ranges therebetween. In some embodiments, L R It can be about 1 cm, about 2 cm, about 3 cm, about 4 cm, about 5 cm, about 6 cm, about 7 cm, about 8 cm, about 9 cm, about 10 cm, about 20 cm, about 30 cm, about 40 cm, about 50 cm, about 60 cm, about 70 cm, about 80 cm, about 90 cm or about 1 m.

[0042] In some embodiments, W R It can be at least about 5 mm, at least about 6 mm, at least about 7 mm, at least about 8 mm, at least about 9 mm, at least about 1 cm, at least about 2 cm, at least about 3 cm, at least about 4 cm, at least about 5 cm, at least about 6 cm, at least about 7 cm, at least about 8 cm, at least about 9 cm, at least about 10 cm, at least about 20 cm, at least about 30 cm, or at least about 40 cm. In some embodiments, W R And / or Wc can be no more than about 50cm, no more than about 40cm, no more than about 30cm, no more than about 20cm, no more than about 10cm, no more than about 9cm, no more than about 8cm, no more than about 7cm, no more than about 6cm, no more than about 5cm, no more than about 4cm, no more than about 3cm, no more than about 2cm, no more than about 1cm, no more than about 9mm, no more than about 8mm, no more than about 7mm or no more than about 6mm. The combination of the above widths is also possible (for example, at least about 5mm and no more than about 50cm or at least about 2cm and no more than about 10cm), including all values ​​and ranges therebetween. In some embodiments, Wc can be no more than about 50cm, no more than about 40cm, no more than about 30cm, no more than about 20cm, no more than about 10cm, no more than about 9cm, no more than about 8cm, no more than about 7cm, no more than about 6cm, no more than about 5cm, no more than about 4cm, no more than about 3cm, no more than about 2cm, no more than about 1cm, no more than about 9mm, no more than about 8mm, no more than about 7mm or no more than about 6mm. RIt can be about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 1 cm, about 2 cm, about 3 cm, about 4 cm, about 5 cm, about 6 cm, about 7 cm, about 8 cm, about 9 cm, about 10 cm, about 20 cm, about 30 cm, about 40 cm or about 50 cm.

[0043] As shown, the groove 372 is along the W R Extending horizontally, the gaps between the grooves 372 are along W R and L R , so that the current is directed through a specific path on the resistive member 370. The grooves 372 form tortuosity in the flow path of the electrons flowing through the resistive member 370. The tortuosity is defined as the ratio of the length of the actual flow path (the length of the path of the current flowing through the resistive member 370) to the straight-line distance between the ends of the flow path (the direct length from the positive terminal of the resistive member 370 to the negative terminal of the resistive member 370). Therefore, by adding more grooves 372, the tortuosity of the resistive member 370 can be increased. The tortuosity can be proportional to the impedance of the resistive member 370, and the impedance of the resistive member 370 can be proportional to the heat generated when a certain amount of current passing through the resistive member 370 is given. The resistive member 370 with more grooves 372 included can generate a greater amount of heat than the resistive member 370 with fewer grooves included or without grooves. In addition, the inclusion of grooves 372 can increase the surface area of ​​the resistive member 370, thereby increasing the ability of the resistive member 370 to dissipate heat. In some embodiments, the resistive member 370 can include more than one sheet or foil. In some embodiments, the resistive member 370 can be a continuous sheet or foil without grooves or channels 372.

[0044] The resistive member 370 can have a tortuosity of at least about 1, at least about 1.5, at least about 2, at least about 2.5, at least about 3, at least about 3.5, at least about 4, at least about 4.5, at least about 5, at least about 5.5, at least about 6, at least about 6.5, at least about 7, at least about 7.5, at least about 8, at least about 8.5, at least about 9, at least about 9.5, at least about 10, at least about 20, at least about 30, at least about 40. In some embodiments, the tortuosity can be no more than about 50, no more than about 40, no more than about 30, no more than about 20, no more than about 10, no more than about 9.5, no more than about 9, no more than about 8.5, no more than about 8, no more than about 7.5, no more than about 7, no more than about 6.5, no more than about 6, no more than about 5.5, no more than about 5, no more than about 4.5, no more than about 4, no more than about 3.5, no more than about 3, no more than about 2.5, no more than about 2, no more than about 1.5. Combinations of the above widths are also possible (eg, at least about 5 and no more than about 50 or at least about 2 and no more than about 10), including all values ​​and ranges therebetween. In some embodiments, the tortuosity can be about 1, about 1.25, about 1.5, about 1.75, about 2, about 2.25, about 2.5, about 2.75, about 3, about 3.25, about 3.5, about 3.75, about 4, about 4.25, about 4.5, about 4.75, about 5, about 5.25, about 5.5, about 5.75, about 6, about 6.25, about 6.5, about 6.75, about 7, about 7.25, about 7.5, about 7.75, about 8, about 8.25, about 8.5, about 8.75, about 9, about 9.25, about 9.5, about 9.75, about 10 cm, about 20 cm, about 30 cm, about 40 cm, or about 50 cm.

[0045] In some embodiments, the resistive member 370 may include a partially conductive, high resistance material (e.g., low carbon loading slurry, alumina, ceramic composites, etc.) such that current flowing between the resistive member 370 and the anode current collector 320 and / or cathode current collector 340 produces the desired heating. In some embodiments, the resistive member 370 may include a highly conductive, low resistance material (e.g., high carbon loading, metal fillers, conductive epoxy, etc.) such that current flowing through the surface of the resistive member 370 produces the desired heating.

[0046] The resistive member 370 may include a coating of a conductive material 368 on at least one of the first side and the second side of the resistive member 370. Figure 3A and Figure 3BAs shown, the conductive material 368 is coated on a first side of the resistive member 370, which is adjacent to the cathode current collector 340 and other electrically active components of the electrochemical cell 300. In some embodiments, the conductive material can be coated on a second side of the resistive member 370, which is opposite the first side (i.e., the second side faces the pouch 380 and the exterior of the electrochemical cell 300). In some embodiments, the conductive material 368 can coat both sides of the resistive member 370. In some embodiments, the conductive material 368 can coat the first side of the insulating material 368. In some embodiments, the conductive material 368 can include carbon-based materials, conductive metals and / or non-metallic materials, including composite materials or layered materials. In some embodiments, the conductive material 368 can include, for example, graphite, carbon powder, pyrolytic carbon, carbon black, carbon fibers, carbon microfibers, carbon nanotubes (CNTs), single-walled CNTs, multi-walled CNTs, fullerene carbons including "bucky balls", graphene sheets and / or aggregates of graphene sheets, any other conductive material, metal, alloy, or combination thereof.

[0047] Any suitable method may be used to coat the resistive member 370 with the conductive material 368, including but not limited to vapor deposition, chemical vapor deposition, physical vapor deposition, atomic layer deposition, metal organic chemical vapor deposition, nitrogen plasma assisted deposition, sputter deposition, reactive sputter deposition, electroless deposition, spray deposition, sputtering, melt quenching, mechanical milling, spraying, cold spray process, plasma deposition process, electrochemical deposition, sol gel process, evaporation, or any combination thereof. In some embodiments, the conductive coating 368 may be applied to the resistive member 370 via a liquid coating process (such as applying a liquid slurry or paint) or an extrusion process with or without a hot / cold pressing process. In some embodiments, the conductive material 368 may be applied to the diaphragm via casting, lamination, calendaring, dripping, pressing, rolling, casting, or any combination thereof. In some embodiments, the conductive material 368 may be applied via any of the methods described in the '351 Publication and / or the '705 Publication. When current passes through the resistive member 370, the conductive material 368 may facilitate or enhance the heating of the heating element 360. In some embodiments, conductive material 368 may be a separate layer from resistive member 370 .

[0048] In some embodiments, the conductive material 368 may have a thickness of at least about 100 nm, at least about 200 nm, at least about 300 nm, at least about 400 nm, at least about 500 nm, at least about 600 nm, at least about 700 nm, at least about 800 nm, at least about 900 nm, at least about 1 μm, at least about 2 μm, at least about 3 μm, at least about 4 μm, at least about 5 μm, at least about 6 μm, at least about 7 μm, at least about 8 μm, at least about 9 μm, at least about 10 μm, at least about 11 μm, at least about 12 μm, at least about 13 μm, at least about 14 μm, at least about 15 μm, at least about 16 μm, at least about 17 μm, at least about 18 μm, or at least about 19 μm. In some embodiments, when disposed on the first side and / or the second side of the resistive member 370, the conductive material 368 may have a thickness of no more than about 20 μm, no more than about 19 μm, no more than about 18 μm, no more than about 17 μm, no more than about 16 μm, no more than about 15 μm, no more than about 14 μm, no more than about 13 μm, no more than about 12 μm, no more than about 11 μm, no more than about 10 μm, no more than about 9 μm, no more than about 8 μm, no more than about 7 μm, no more than about 6 μm, no more than about 5 μm, no more than about 4 μm, no more than about 3 μm, no more than about 2 μm, no more than about 1 μm, no more than about 900 nm, no more than about 800 nm, no more than about 700 nm, no more than about 600 nm, no more than about 500 nm, no more than about 400 nm, no more than about 300 nm, or no more than about 200 nm. Combinations of the above thicknesses of conductive material 368 are also possible (e.g., at least about 100 nm and no more than about 20 μm or at least about 1 μm and no more than about 5 μm), including all values ​​and ranges therebetween. In some embodiments, when disposed on the first side and / or the second side of resistive member 370, conductive material 368 can have a thickness of about 100 nm, about 200 nm, about 300 nm, about 400 nm, about 500 nm, about 600 nm, about 700 nm, about 800 nm, about 900 nm, about 1 μm, about 2 μm, about 3 μm, about 4 μm, about 5 μm, about 6 μm, about 7 μm, about 8 μm, about 9 μm, about 10 μm, about 11 μm, about 12 μm, about 13 μm, about 14 μm, about 15 μm, about 16 μm, about 17 μm, about 18 μm, about 19 μm, or about 20 μm.

[0049] In some embodiments, conductive material 368 may have a g / cm 3 , at least about 1.3 g / cm 3 , at least about 1.4 g / cm 3 , at least about 1.5 g / cm 3 , at least about 1.6 g / cm 3, at least about 1.7 g / cm 3 , at least about 1.8 g / cm 3 or at least about 1.9 g / cm 3 In some embodiments, the conductive material 368 may have a density of no more than about 2 g / cm 3 , not more than about 1.9g / cm 3 , not more than about 1.8g / cm 3 , not more than about 1.7g / cm 3 , not more than about 1.6g / cm 3 , not more than about 1.5g / cm 3 , not more than about 1.4g / cm 3 or not more than about 1.3g / cm 3 Combinations of the above densities of conductive material 368 are also possible (e.g., at least about 1.2 g / cm 3 And not more than about 2g / cm 3 or at least about 1.3 g / cm 3 And not more than about 2g / cm 3 ), including all values ​​and ranges therebetween. In some embodiments, the conductive material 368 may have a thickness of about 1.2 g / cm 3 , about 1.3g / cm 3 , about 1.4g / cm 3 , about 1.5g / cm 3 , about 1.6g / cm 3 , about 1.7g / cm 3 , about 1.8g / cm 3 , about 1.9g / cm 3 or about 2g / cm 3 density.

[0050] In some embodiments, conductive material 368 may include particles having an average particle size (i.e., D50) of at least about 10 nm, at least about 20 nm, at least about 30 nm, at least about 40 nm, at least about 50 nm, at least about 60 nm, at least about 70 nm, at least about 80 nm, at least about 90 nm, at least about 100 nm, at least about 200 nm, at least about 300 nm, at least about 400 nm, at least about 500 nm, at least about 600 nm, at least about 70 nm, at least about 80 nm, at least about 90 nm, at least about 100 nm, at least about 200 nm, at least about 300 nm, at least about 400 nm, at least about 500 nm, at least about 600 nm, at least about 700nm, at least about 800nm, at least about 900nm, at least about 1μm, at least about 2μm, at least about 3μm, at least about 4μm, at least about 5μm, at least about 6μm, at least about 7μm, at least about 8μm, at least about 9μm, at least about 10μm, at least about 11μm, at least about 12μm, at least about 13μm, at least about 14μm, at least about 15μm, at least about 16μm, at least about 17μm, at least about 18μm or at least about 19μm. In some embodiments, conductive material 368 may include particles having an average particle size of no more than about 20 μm, no more than about 19 μm, no more than about 18 μm, no more than about 17 μm, no more than about 16 μm, no more than about 15 μm, no more than about 14 μm, no more than about 13 μm, no more than about 12 μm, no more than about 11 μm, no more than about 10 μm, no more than about 9 μm, no more than about 8 μm, no more than about 7 μm, no more than about 6 μm, no more than about 5 μm, no more than about 4 μm, no more than about 8 μm, no more than about 10 μm, no more than about 15 ... about 3 μm, no more than about 2 μm, no more than about 1 μm, no more than about 900 nm, no more than about 800 nm, no more than about 700 nm, no more than about 600 nm, no more than about 500 nm, no more than about 400 nm, no more than about 300 nm, no more than about 200 nm, no more than about 100 nm, no more than about 90 nm, no more than about 80 nm, no more than about 70 nm, no more than about 60 nm, no more than about 50 nm, no more than about 40 nm, no more than about 30 nm or no more than about 20 nm.

[0051] Combinations of the above-recited particle sizes are also possible (eg, at least about 10 nm and no more than about 20 μm or at least about 1 μm and no more than about 5 μm), including all values ​​and ranges therebetween. In some embodiments, the conductive material 368 may include particles having an average particle size of about 10 nm, about 20 nm, about 30 nm, about 40 nm, about 50 nm, about 60 nm, about 70 nm, about 80 nm, about 90 nm, about 100 nm, about 200 nm, about 300 nm, about 400 nm, about 500 nm, about 600 nm, about 700 nm, about 800 nm, about 900 nm, about 1 μm, about 2 μm, about 3 μm, about 4 μm, about 5 μm, about 6 μm, about 7 μm, about 8 μm, about 9 μm, about 10 μm, about 11 μm, about 12 μm, about 13 μm, about 14 μm, about 15 μm, about 16 μm, about 17 μm, about 18 μm, or about 19 μm, or about 20 μm.

[0052] The heating element may include an insulating material 365. In some embodiments, a conductive material 368 may coat a first side of the insulating material 368, the first side of the insulating material 368 facing the resistive member 370. The resistive member 370 may be encapsulated in an electrically insulating layer or assembly or co-encapsulated with the electrochemical cell 300. In some embodiments, the insulating material 365 may be a pouch surrounding the resistive member 370 and the conductive material 368, or a single layer disposed between the resistive member 370 and other components of the electrochemical cell 300. The insulating material 365 may be used to isolate the conductive coating 368 from the electrical components of the electrochemical cell 300 (e.g., terminals, electrodes, active materials, electrolytes, etc.). The insulating material 365 may be made of any suitable material including, for example, polycarbonate, polyethylene, polypropylene, polyimide, mica, polystyrene, fiberglass, FORMEX TM , any other suitable insulating material, or a combination thereof). In some embodiments, the heating element may include a plurality of resistive members 360 disposed in insulating material 365. In some embodiments, the heating element may include about 2 resistive members, 3 resistive members, 4 resistive members, 5 resistive members, 6 resistive members, 7 resistive members, 8 resistive members, 9 resistive members, or 10 resistive members.

[0053] In some embodiments, the electrochemical cell 300 can be placed in an insulating pouch 380. The insulating pouch 380 can have a first film placed on the heating element 360 and a second film placed below the anode current collector 320, the first film and the second film connected together to form a pouch. In some embodiments, the heating element 360 can be placed on the outer surface of the insulating pouch 380 instead. In some embodiments, the heating element 360 including the resistive member 370 and the conductive material 368 can be integrated into the insulating pouch 380. In some embodiments, the conductive material 368 is integrated into the inner surface of the insulating pouch 380 or deposited on the inner surface of the insulating pouch. In some embodiments, the conductive material 368 is integrated into the outer surface of the insulating pouch 380 or deposited on the outer surface of the insulating pouch. The insulating pouch 380 can prevent unwanted current from passing between multiple electrochemical cells connected in series during operation of the electrochemical cell. The insulating pouch 380 can be made of any suitable material (including, for example, polycarbonate, polyethylene, polypropylene, polyimide, mica, polystyrene, fiberglass, FORMEX TM , any other suitable insulating material or combination thereof). The electrochemical cell 300 and the insulating pouch 380 can be placed in a structure such as an outer pouch, a shell or a housing (not shown). In some embodiments, a plurality of electrochemical cells can be housed in a stacked body pouch (not shown). In some embodiments, the stacked body pouch can include an aluminized pouch. In some embodiments, the heating element 360 can be placed on the outer surface of the stacked body pouch instead. In some embodiments, a heating element including a resistive member 360 and a conductive material 368 can be integrated into the stacked body pouch. In some embodiments, the conductive material 368 can be integrated into the inner surface of the stacked body pouch. In some embodiments, the conductive material 368 can be integrated into the outer surface of the stacked body pouch.

[0054] As shown, the cathode current collector 340, the resistive member 370 and the conductive material 368 can extend away from or extend outward from the first end of the electrochemical cell 300, thereby forming one or more pole ears that can be approached from the outside of the outer pouch. In some embodiments, the anode current collector 320 may include a pole ear extending away from or extending outward from the first end of the electrochemical cell 300. The pole ear can be used as a voltage measurement point for battery monitoring, or as a connection point through which the electrochemical cell 300 can be electrically connected to other electrochemical cells in series. The pole ear can also be used as a connection point through which the electrochemical cell 300 can be connected to an electronic circuit (such as a battery management system (BMS) (not shown)). The BMS may include a circuit board (PCB or PCBA) and can be used, for example, to control the current through the battery cell to monitor the battery cell, balance the battery cell, or control the heat generated by the battery cell. In some embodiments, the balance of the electrochemical cell 300 can be performed at the pole ear via the BMS.

[0055] When the electrochemical cell is part of an electrochemical cell stack, the balance of the electrochemical cell 300 may be beneficial. Balancing involves removing charge from the electrochemical cell 300 or adding charge to the electrochemical cell (e.g., balancing current) to ensure that the voltage of any electrochemical cell in the electrochemical cell does not deviate from the battery pack. Balancing electrochemical cells may generate heat, which can be absorbed by the PCB of the BMS. The design of the electrochemical cell 300 can contribute to the distribution of thermal energy. The design can then allow an increase in the current available for balancing. The amount of available balancing current can be proportional to the cell capacity. Through the design of the electrochemical cell 300, the balancing current can be adjusted to meet the voltage requirements of the system and manage the temperature of the system. The increased thermal mass can contribute to the dissipation of the balancing current. The thermal mass can be proportional to the available balancing energy. In some embodiments, an existing cooling system (not shown) can remove heat from the electrochemical cell 300. The incorporation of the heating element 370 can reduce the number of components required at the module and battery pack level (e.g., heat pads and / or water heaters can be excluded). The heating element also results in increased heating efficiency, with less loss to the surrounding environment (ie, heat goes directly to the electrochemical cell 300).

[0056] In some embodiments, the heating element may result in a marginal increase in system cost (i.e., the additional cost of the additional conductive material and carbon). However, the manufacturing method can be implemented without new equipment. In some embodiments, the construction of the electrochemical cell 300 can use existing connection methods used for battery cell production, with one additional connection for the heating element 370. In some embodiments, the resistive member 370 can be purchased in an existing form from a service application (such as food packaging containing an aluminum film layer) or a battery cell pouch material supplier to further reduce manufacturing complexity and cost.

[0057] FIG. 4A to FIG. 4B is a diagram of an electrochemical cell 400 including a heating element 460 according to an embodiment. Figure 4A A cross-sectional profile view of the elements of an electrochemical cell 400 is shown. Figure 4B An exploded view of an electrochemical cell 400 is shown. Figure 4A As shown, the electrochemical cell 400 includes: an anode material 410, which is disposed on an anode current collector 420; a cathode material 430, which is disposed on a cathode current collector 440; and a separator 450, which is disposed between the anode material 410 and the cathode material 430. The electrochemical cell 400 further includes: a resistive member 470, which has a conductive material 468 disposed on a first side of the resistive member 470; an insulating material 465, which is disposed between the resistive member 470 and the cathode current collector 440; and a pouch material 480, which is disposed around the electrochemical cell 400. The electrochemical cell 400 includes a first end and a second end. The cathode current collector 440, the resistive member 470 and / or the conductive material 468 can extend away from or outward from the first end of the electrochemical cell 400 to form one or more tabs.

[0058] like Figure 4B As shown, the resistive member 470 may be a sheet or foil of conductive material where sections of the sheet or foil are completely removed (eg, cuts, holes, gaps) to change the impedance of the resistive member 470. The resistive member 470 has a length L R and width W R Similar to the grooves described above, the cutouts 472 may be removed in a specific pattern to change the impedance of the resistive member 470, thereby allowing a predetermined amount of heat to be generated by the resistive member 470 given a certain amount of current passing through the electrochemical cell 400. As shown, the resistive member may be removed along the W RHorizontally extending segments allow current to be directed through a specific path on the resistive member 470. The function of the cutout 472 is similar to that of the groove 372, enabling the tortuosity of the conductive material to be adjusted. By adjusting the manner in which segments are removed from the resistive member 470, the tortuosity of the resistive member 470 can be increased, thereby increasing the ability of the resistive member 470 to generate heat. The resistive member 470 with the cutout 473 can generate a greater amount of heat than a resistive member with fewer or no cutouts. The resistive member 470 can be purchased in an existing form from a service application (such as food packaging containing an aluminum film layer) or a battery cell pouch material supplier to reduce manufacturing complexity and cost. The segments of the resistive member 470 can be removed using standard PCB manufacturing methods or using standard flexible circuit technology.

[0059] The resistive member 470 can have a tortuosity of at least about 1, at least about 1.5, at least about 2, at least about 2.5, at least about 3, at least about 3.5, at least about 4, at least about 4.5, at least about 5, at least about 5.5, at least about 6, at least about 6.5, at least about 7, at least about 7.5, at least about 8, at least about 8.5, at least about 9, at least about 9.5, at least about 10, at least about 20, at least about 30, at least about 40, at least about 50. In some embodiments, the tortuosity can be no more than about 50, no more than about 40, no more than about 30, no more than about 20, no more than about 10, no more than about 9, no more than about 8, no more than about 7, no more than about 6, no more than about 5, no more than about 4, no more than about 3, no more than about 2, no more than about 1. Combinations of the above widths are also possible (e.g., at least about 5 and no more than about 50 or at least about 2 and no more than about 10), including all values ​​and ranges therebetween. In some embodiments, the tortuosity can be about 1, about 1.25, about 1.5, about 1.75, about 2, about 2.25, about 2.5, about 2.75, about 3, about 3.25, about 3.5, about 3.75, about 4, about 4.25, about 4.5, about 4.75, about 5, about 5.25, about 5.5, about 5.75, about 6, about 6.25, about 6.5, about 6.75, about 7, about 7.25, about 7.5, about 7.75, about 8, about 8.25, about 8.5, about 8.75, about 9, about 9.25, about 9.5, about 9.75, about 10 cm, about 20 cm, about 30 cm, about 40 cm, or about 50 cm.

[0060] In some embodiments, anode 410, anode current collector 420, cathode 430, cathode current collector 440, separator 450, resistive member 470, conductive material 468, and insulating material 465 may be the same or substantially similar to anode 310, anode current collector 320, cathode 330, cathode current collector 340, separator 350, resistive member 370, conductive material 368, and insulating material 365 as described above with reference to FIG 3. Therefore, certain aspects of anode 410, anode current collector 420, cathode 430, cathode current collector 440, and separator 450, resistive member 470, conductive material 468, and insulating material 465 are not described in more detail herein.

[0061] FIG. 5A to FIG. 5B is an illustration of an electrochemical cell 500 including a heating element 560 according to an embodiment. Figure 5A A cross-sectional profile view of the elements of electrochemical cell 500 is shown. Figure 5B An exploded view of an electrochemical cell 500 is shown. Figure 5A As shown, the electrochemical cell 500 includes an anode material 510 disposed on an anode current collector 520, a cathode material 530 disposed on a cathode current collector 540, and a separator 550 disposed between the anode material 510 and the cathode material 430. The electrochemical cell 500 further includes: a resistive member 570 having a conductive material 568 coating the resistive member 570; an insulating material 565 disposed between the resistive member 570 and the cathode current collector 540; and a pouch material 580 disposed around the electrochemical cell 500. The electrochemical cell 500 includes a first end and a second end. The cathode current collector 540, the resistive member 570, and / or the conductive material 568 can extend away from or outwardly from the first end of the electrochemical cell 500 to form one or more tabs.

[0062] In some embodiments, the resistive member 570 can be a wire having a first terminal end connected in series with the current collector and a second terminal end extending away from or outward from the first end of the electrochemical cell 500, the wire following a circuitous (tortuous, twisted) path. The characteristics of the wire, such as the cross-sectional area, length, and path, can be adjusted to change the impedance of the resistive member 570. The wire can be coated with a conductive material 568. By adjusting the path of the wire, the tortuosity of the resistive member 570 can be increased, thereby increasing the ability of the resistive member 570 to generate heat. In addition, adjusting the cross-sectional area of ​​the wire can also be used to adjust the impedance of the resistive member 570. At a shorter length L R A resistive member 570 having a greater number of turns and / or a smaller cross-sectional area may generate a greater amount of heat than a resistive member having fewer turns and / or a larger cross-sectional area.

[0063] In some embodiments, the anode 510, the anode current collector 520, the cathode 530, the cathode current collector 540, the separator 550, the resistive member 570, the conductive material 568, and the insulating material 565 may be the same or substantially similar to the anode 310, the anode current collector 320, the cathode 330, the cathode current collector 340, the separator 350, the resistive member 370, the conductive material 368, and the insulating material 365 as described above with reference to FIG 3. Therefore, certain aspects of the anode 510, the anode current collector 520, the cathode 530, the cathode current collector 540, and the separator 550, the resistive member 570, the conductive material 568, and the insulating material 565 are not described in more detail herein.

[0064] Fig. 6A A circuit diagram of an electrochemical cell stack 6000 including a heating element is shown, wherein the electrochemical cells are connected in parallel. As shown, the heating element can provide an electrical connection between the negative terminal of the electrochemical cell and the BMS to reduce connection points. In some embodiments, a first terminal end of the heating element can be electrically connected to the electrochemical cell, and a second terminal end of the heating element can be electrically connected to the BMS. Figure 6B is a circuit diagram of an electrochemical cell 600 having a heating element 660 that generates heat when the electrochemical cell 600 is balanced. As shown, the electrochemical cell 600 has current diversion due to the implementation of the heating element 660.

[0065] Figure 7 360 is a schematic flow chart of a method for heating an electrochemical cell having a heating element according to an embodiment. Although described with respect to an electrochemical cell 300 including a resistive member 370, a conductive material 368, and an insulating material 365, the method 700 is equally applicable to any electrochemical cell including any heating element described herein. All such variations should be considered within the scope of the present disclosure.

[0066] Method 700 includes etching the outer surface of the resistive member 370 at 702 so that the resistive member 370 has a desired impedance. In some embodiments, a section of the resistive member 370 may be completely removed to change the impedance of the resistive member 370. In some embodiments, the resistive member 370 may instead include a wire having a first terminal end, which is connected in series with the current collector 340 of the electrochemical cell 300 and forms a circuitous path with a second terminal end extending horizontally outward from the electrochemical cell 300. At 704, the method includes coating the resistive member 370 with a conductive coating 368. At 706, the resistive member 370 may be disposed in an insulating material 365 to isolate the conductive material 368 from the electrical components of the cell. In some embodiments, the insulating material 365 may be a single layer disposed between the resistive member 370 and the current collector 340 of the electrochemical cell 300. In some embodiments, the insulating material 365 may be a small bag disposed around the resistive member 370. At 708, the method includes placing a resistive member 370 on a first side of the cathode current collector 340. In some embodiments, the heating element is electrically connected to the cathode current collector 340 and is adjacent to the cathode current collector 340 in the circuit. In some embodiments, the heating element can be electrically connected to the anode current collector 320 and can be adjacent to the anode current collector 320 in the circuit. At 710, an electronic circuit electrically coupled to the resistive member 370 is used to control the current flowing through the resistive member 370 so that the temperature of the resistive member 370 increases. In some embodiments, the electronic circuit can be an already existing BMS including a PCB. In some embodiments, the BMS can be used to monitor the electrochemical cells 300, balance the electrochemical cells 300, and send current through the electrochemical cells 300 to generate heat. In some embodiments, the BMS can include an existing cooling system, which can be used to cool the electrochemical cells 300 when heat is generated during the balancing of the electrochemical cells 300.

[0067] Various concepts can be implemented as one or more methods, wherein at least one example has been provided. The actions performed as part of the method can be ordered in any suitable manner. Therefore, such an embodiment can be constructed in which the actions are performed in an order different from the order shown, which may include performing some actions simultaneously, even if the action is shown as a continuous action in the illustrative embodiment. In other words, it should be understood that such features are not necessarily limited to a specific execution order, but any number of threads, processes, services, servers and / or etc. that can be performed in series, asynchronously, concurrently, in parallel, simultaneously, synchronously and / or in a manner consistent with the present disclosure. Therefore, some of these features may contradict each other because these features cannot exist in a single embodiment at the same time. Similarly, some features are applicable to one aspect of the innovation and are not applicable to other aspects.

[0068] In addition, the present disclosure may include other innovations not currently described. Applicants reserve all rights to such innovations, including the right to embody such innovations, submit additional applications, continuations, partial continuations, divisions, and / or the like. Therefore, it should be understood that the advantages, embodiments, examples, functions, features, logic, operations, organizations, structures, topologies, and / or other aspects of the present disclosure should not be considered as limitations on the present disclosure as defined by the embodiments or limitations on the equivalents of the embodiments. Depending on the specific expectations and / or characteristics of individual and / or enterprise users, database configurations and / or relational models, data types, data transmissions, and / or network architectures, grammatical structures, and / or the like, the various embodiments of the technology disclosed herein can be implemented in a manner that realizes a large amount of flexibility and customization as described herein.

[0069] All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and / or ordinary meanings of the defined terms.

[0070] As used herein, in particular embodiments, the term "about" or "approximately" when preceding a numerical value represents a range of plus or minus 10% of the value. Where a range of values ​​is provided, it is understood that, unless the context clearly indicates otherwise, each intermediate value (to one-tenth of the unit of the lower limit) between the upper and lower limits of the range and any other stated values ​​or intermediate values ​​within the range are included in the present disclosure. The upper and lower limits of these smaller ranges can be independently included in smaller ranges and are also included in the present disclosure, subject to any specific exclusion limits within the range. Where the stated range includes one or two of the limits, the range excluding any one or two of the included limits is also included in the present disclosure.

[0071] The phrase "and / or" used herein in the specification and examples should be understood to mean "either or both" of the elements so combined, i.e., elements that exist jointly in some cases and separately in other cases. Multiple elements listed with "and / or" should be understood in the same way, i.e., "one or more" of the elements so combined. In addition to the elements specifically identified by the "and / or" clause, other elements may optionally be present, whether related or unrelated to those specifically identified. Therefore, as a non-limiting example, when used in conjunction with open language such as "including", reference to "A and / or B" may refer to only A (optionally including elements other than B) in one embodiment; in another embodiment, only B (optionally including elements other than A); in yet another embodiment, both A and B (optionally including other elements); etc.

[0072] As used herein in the specification and in the embodiments, "or" should be understood to have the same meaning as the meaning of "and / or" as defined above. For example, when the items in the list are separated, "or" or "and / or" should be interpreted as inclusive, that is, including at least one element in multiple elements or element lists, but also including more than one element, and optionally other unlisted items. Only explicitly point out the opposite terms such as "only one of ..." or "exactly one of ..." or when used in the embodiments, "consisting of ..." will refer to including exactly one element in many elements or element lists. In general, when there are exclusive terms before, such as "any one", "one of ...", "only one of ..." or "exactly one of ...", the term "or" as used herein should only be interpreted as indicating exclusive alternatives (that is, "one or other one, not two"). When used in the embodiments, "essentially consisting of ..." should have its ordinary meaning as used in the field of patent law.

[0073] As used herein in the specification and in the examples, the phrase "at least one" of a list of one or more elements is understood to mean at least one element selected from any one or more elements in the list of elements, but does not necessarily include at least one of each element specifically listed in the list of elements, and does not exclude any combination of elements in the list of elements. This definition also allows for the optional presence of elements in addition to the elements specifically identified in the list of elements to which the phrase "at least one" refers, whether related to or unrelated to the specifically identified elements. Thus, as a non-limiting example, "at least one of A and B" (or equivalently, "at least one of A or B", or equivalently, "at least one of A and / or B") can refer to at least one in one embodiment, optionally including more than one A, without B (and optionally including elements other than B); in another embodiment, refers to at least one, optionally including more than one B, without A (and optionally including elements other than A); in yet another embodiment, refers to at least one, optionally including more than one A, and at least one, optionally including more than one B (and optionally including other elements); etc.

[0074] In the examples and in the above description, all transitional phrases such as "comprising", "including", "carrying", "having", "containing", "involving", "holding", "comprising", etc. should be understood as open-ended, i.e., meaning including but not limited to. As described in Section 2111.03 of the Manual of Patent Examining Procedures of the United States Patent Office, only the transitional phrases "consisting of" and "consisting essentially of" should be closed or semi-closed transitional phrases, respectively.

[0075] Although specific embodiments of the present disclosure have been summarized above, many substitutions, modifications and variations are apparent to those skilled in the art. Therefore, the embodiments set forth herein are intended to be illustrative rather than restrictive. Various changes may be made without departing from the spirit and scope of the present disclosure. Where the above methods and steps indicate specific events occurring in a particular order, those of ordinary skill in the art who benefit from the present disclosure will recognize that the order of specific steps may be modified, and such modifications are variations according to the present invention. In addition, as described above, certain steps in the steps may be performed simultaneously in a parallel process, as well as sequentially, where possible. Embodiments have been specifically shown and described, but it will be appreciated that various changes in form and detail may be made.

Claims

1. An electrochemical cell comprising: Anode current collector; an anode material, the anode material being disposed on the anode current collector; cathode current collector; a cathode material disposed on a first side of the cathode current collector; a separator disposed between the anode material and the cathode material; as well as A heating element is disposed on a second side of the cathode current collector, the second side being opposite to the first side, the heating element comprising an electrically conductive material and an electrically insulating material.

2. The electrochemical cell of claim 1, wherein the conductive material comprises a metal sheet including etched grooves for dissipation of heat.

3. The electrochemical cell of claim 1, wherein the conductive material comprises a metal wire comprising a first terminal end in contact with the cathode current collector and a second terminal end extending away from the electrochemical cell.

4. The electrochemical cell of claim 1, wherein the conductive material comprises a planar sheet of metal with sections removed to form a flow path for the flow of electrical current.

5. The electrochemical cell of claim 1, wherein the heating element further comprises a conductive material.

6. The electrochemical cell of claim 5, wherein the conductive material comprises at least one of graphite, carbon powder, pyrolytic carbon, carbon black, carbon fibers, carbon microfibers, carbon nanotubes, fullerene carbon, and one or more graphene sheets.

7. The electrochemical cell of claim 1, wherein the conductive material comprises at least one of aluminum or copper.

8. The electrochemical cell of claim 1, further comprising: a first film disposed on the heating element; as well as A second membrane is disposed on the anode current collector, the second membrane being coupled to the first membrane to form a pouch.

9. The electrochemical cell of claim 1, further comprising: a first film disposed between the heating element and the cathode current collector; as well as A second membrane is disposed on the anode current collector, the second membrane is coupled to the first membrane to form a pouch, the heating element being disposed outside of the pouch.

10. The electrochemical cell of claim 1, further comprising: a first film disposed on the heating element; as well as A second film is disposed on the second current collector, the second film being coupled to the first film to form a pouch.

11. The electrochemical cell of claim 1 , further comprising: a first film disposed between the heating element and a first current collector; as well as A second film is disposed on the second current collector, the second film is coupled to the first film to form a pouch, the heating element being disposed outside of the pouch.

12. The electrochemical cell of claim 1, further comprising: a first film disposed on the heating element; as well as A second film is disposed on the second current collector, the second film being coupled to the first film to form a pouch.

13. The electrochemical cell of claim 1, further comprising: a first film disposed between the heating element and a first current collector; as well as A second film is disposed on the second current collector, the second film is coupled to the first film to form a pouch, the heating element being disposed outside of the pouch.

14. An electrochemical cell comprising: First Collector Fluid; a first electrode material disposed on a first side of the first current collector; Second episode fluid; a second electrode material, the second electrode material being disposed on the second current collector; a separator disposed between the first electrode material and the second electrode material; an insulating layer disposed on a second side of the first current collector, the second side being opposite to the first side; as well as A metal sheet is disposed on the insulating layer and electrically coupled in series with the first current collector, wherein the metal sheet comprises a groove for dissipating heat.

15. The electrochemical cell of claim 14, further comprising: A conductive material is disposed on the metal sheet.

16. The electrochemical cell of claim 14, wherein the conductive material comprises at least one of graphite, carbon powder, pyrolytic carbon, carbon black, carbon fibers, carbon microfibers, carbon nanotubes, fullerene carbon, and one or more graphene sheets.

17. The electrochemical cell of claim 14, wherein the metal sheet comprises at least one of aluminum or copper.

18. An electrochemical cell comprising: First Collector Fluid; a first electrode material disposed on a first side of the first current collector; Second episode fluid; a second electrode material, the second electrode material being disposed on the second current collector; a separator disposed between the first electrode material and the second electrode material; an insulating layer disposed on a second side of the first current collector, the second side being opposite to the first side; as well as A metal wire is disposed inside the insulating layer along a circuitous path, and the metal wire is connected in series with the first current collector.

19. The electrochemical cell of claim 18, wherein the metal wire comprises at least one of aluminum or copper.

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