Device and method for inspecting battery cell

Abstract

A device and a method for inspecting a battery cell are disclosed. The device and method for inspecting a battery cell, according to one embodiment of the present disclosure, may increase the temperature of a battery cell while securing the angle of view of a camera.

Description

Battery cell inspection device and method

[0001] The present disclosure relates to a battery cell inspection device and method.

[0002] Battery cells, as secondary cells, may contain electrolyte. If the electrolyte leaks outside the battery cell, the performance of the battery cell may deteriorate and its safety may be compromised. Therefore, it is necessary to inspect the battery cell for electrolyte leakage.

[0003] An object of the present disclosure may be to provide a battery cell inspection device and method that secures a camera's field of view and increases the temperature of a battery cell.

[0004] A battery cell inspection device according to the present disclosure comprises: a carrier forming an upper face; a core camera positioned above the carrier and facing the upper face of the carrier; and a core heater unit positioned between the carrier and the core camera, the core heater unit including a heater module for irradiating infrared rays to the carrier, wherein the core heater unit can form a heater opening through which a field of view of the core camera passes.

[0005] A battery cell inspection method according to the present disclosure may include a heating step of heating a battery cell placed on a carrier; a temperature measuring step of measuring the temperature of the battery cell; a step of comparing the measured temperature with a reference temperature; and a step of inspecting the appearance of the battery cell.

[0006] According to one embodiment of the present disclosure, a battery cell inspection device and method for securing a camera's field of view and increasing the temperature of a battery cell can be provided.

[0007] The battery cell inspection device and method of the present disclosure can be widely applied in green technology fields such as electric vehicles, battery charging stations, and solar and wind power generation using batteries.

[0008] The battery cell inspection device and method of the present disclosure can be used in the manufacture of eco-friendly electric vehicles, hybrid vehicles, etc. to prevent climate change by suppressing air pollution and greenhouse gas emissions.

[0009] Figure 1 is a drawing showing a battery cell mounted on a carrier.

[0010] Fig. 2 is a drawing showing a heater unit and a camera unit arranged on top of the carrier illustrated in Fig. 1.

[0011] Figure 3 is a drawing showing the upper surface of the heater unit.

[0012] Figure 4 is a drawing showing the lower surface of the heater unit illustrated in Figure 3.

[0013] Fig. 5 is a drawing showing the outer heater module and the inner heater module as the lower surface of the heater unit illustrated in Fig. 3.

[0014] Figure 6 is a drawing showing a core heater unit including a plurality of heater modules.

[0015] Figure 7 is a drawing showing a core heater unit and a wing heater unit arranged on top of a carrier.

[0016] FIG. 8 is a block diagram of a battery cell inspection device according to one embodiment of the present disclosure.

[0017] FIG. 9 is a flowchart illustrating a battery cell inspection method according to one embodiment of the present disclosure.

[0018] Hereinafter, the present disclosure will be described in detail with reference to FIGS. 1 to 9. However, these are merely exemplary and the present disclosure is not limited to the specific embodiments described as examples.

[0019] In this specification, the coordinate system may be a Cartesian coordinate system. For example, the forward / backward direction may be parallel to the X-axis. For example, the positive X-axis direction may mean forward. For example, the negative X-axis direction may mean rearward.

[0020] For example, the up-down direction can be parallel to the Z-axis. For example, the positive Z-direction can mean upward. For example, the negative Z-direction can mean downward.

[0021] For example, the left-right direction can be parallel to the Y-axis. For example, the positive Y-axis direction can mean the left side (port side). For example, the negative Y-axis direction can mean the right side (starboard side). The Y-axis can be perpendicular to the X-axis and the Z-axis, respectively.

[0022] Fig. 1 is a drawing showing a battery cell mounted on a carrier. Fig. 2 is a drawing showing a heater unit and a camera unit positioned on the carrier shown in Fig. 1.

[0023] Referring to FIGS. 1 and 2, a battery cell (20) may include a cell body (21) and an electrode lead (22). The cell body (21) may include an electrode assembly (not shown). The electrode assembly (not shown) may be wrapped or sealed, for example, by a pouch.

[0024] For example, the pouch may form the outer surface of the cell body (21). The pouch of the cell body (21) may be formed of a material including a polymer. For example, the outer surface of the pouch of the cell body (21) may be formed of PP (Polypropylene).

[0025] The electrolyte may be placed inside the cell body (21). For example, after the electrolyte is injected into the pouch of the cell body (21), the pouch of the cell body (21) may be sealed.

[0026] If the electrolyte of the cell body (21) leaks to the outside of the cell body (21), the corresponding battery cell (20) may have difficulty performing normal functions. That is, if the electrolyte of the cell body (21) is observed outside of the cell body (21), the corresponding battery cell (20) may be judged to be defective.

[0027] The cell body (21) may extend in the longitudinal direction. For example, the cell body (21) may extend in the front-back direction. For example, the longitudinal direction of the cell body (21) may be the front-back direction. For example, the longitudinal direction of the cell body (21) may be parallel to the X-axis.

[0028] The cell body (21) can form a flat shape. For example, the cell body (21) can form an upper surface and a lower surface. For example, the upper surface of the cell body (21) can face upward, and the lower surface of the cell body (21) can face downward. For example, the thickness of the cell body (21) can be the length of the cell body (21) in the vertical direction.

[0029] The electrode lead (22) may protrude from the cell body (21). For example, the electrode lead (22) may extend from the cell body (21). For example, the electrode lead (22) may protrude from the cell body (21) in the longitudinal direction of the cell body (21). For example, the electrode lead (22) may protrude from at least one of the front face and the rear face of the cell body (21).

[0030] The battery cell inspection device (10) may include a carrier (100). For example, the carrier (100) may transport a battery cell (20). For example, the carrier (100) may form an upper face. The battery cell (20) may be mounted on the upper surface of the carrier (100). The carrier (100) may be movable.

[0031] For example, the lower face of the cell body (21) may face the upper face of the carrier (100) and may be in contact with the upper face of the carrier (100). For example, the upper face of the cell body (21) may face upward. For example, the upper face of the cell body (21) may face at least one of the core camera (201) and the core heater unit (301).

[0032] The side surface of the cell body (21) may extend upward from the lower surface of the cell body (21) and connect to the upper surface of the cell body (21). The side surface of the cell body (21) may form the thickness of the cell body (21). For example, the thickness of the cell body (21) may be the vertical length of the side surface of the cell body (21).

[0033] The side surface of the cell body (21) can form a shape extending in the longitudinal direction of the battery cell (20). For example, the longitudinal direction of the side surface of the cell body (21) can be the front-back direction.

[0034] For example, the end of the side of the cell body (21) may be adjacent to the electrode lead (22). For example, the front edge and the rear edge of the side of the cell body (21) may be adjacent to a pair of electrode leads (22), respectively.

[0035] The battery cell inspection device (10) may include a camera unit (200). For example, the battery cell inspection device (10) may include a core camera (201). The camera unit (200) may include or refer to the core camera (201).

[0036] The core camera (201) may be positioned above the carrier (100). For example, when the battery cell (20) is mounted on the carrier (100), the core camera (201) may be positioned above the battery cell (20).

[0037] The core camera (201) can capture images of the battery cell (20). For example, the core camera (201) can acquire an image of the upper surface of the cell body (21). For example, from the image acquired by the core camera (201), it can be determined whether electrolyte is leaking from the inside of the cell body (21) to the outside of the cell body (21).

[0038] The battery cell inspection device (10) may include a heater unit (300). For example, the battery cell inspection device (10) may include a core heater unit (301). The heater unit (300) may include or refer to the core heater unit (301).

[0039] The core heater unit (301) can be placed on top of the carrier (100). For example, when the battery cell (20) is mounted on the carrier (100), the core heater unit (301) can be positioned on top of the cell body (21).

[0040] The core heater unit (301) may be located below the core camera (201). That is, the core heater unit (301) may be located between the core camera (201) and the cell body (21).

[0041] For example, the core heater unit (301) may be positioned between the core camera (201) and the carrier (100). The core heater unit (301) may form a structure to secure a field of view of the core camera (201) positioned above the core heater unit (301).

[0042] The core heater unit (301) can generate heat. For example, the core heater unit (301) can radiate heat downward. At least a portion of the heat generated by the core heater unit (301) can be transferred to the cell body (21).

[0043] When heat is transferred to the cell body (21), the temperature of the outer surface of the cell body (21) may rise. An image of the cell body (21) in a state where the temperature of the outer surface of the cell body (21) rises may be more advantageous for determining electrolyte leakage than an image of the cell body (21) in a state where the temperature of the outer surface of the cell body (21) is room temperature.

[0044] Fig. 3 is a drawing showing the upper surface of the heater unit. Fig. 4 is a drawing showing the lower surface of the heater unit shown in Fig. 3. Fig. 5 is a drawing showing the lower surface of the heater unit shown in Fig. 3, including an outer heater module and an inner heater module.

[0045] Referring to FIGS. 3 and 4, the core heater unit (301) may include a heater body (310). The heater body (310) may form an upper surface and a lower surface.

[0046] For example, the heater body upper surface (311) may be an upper surface formed on the heater body (310). The heater body upper surface (311) may face the core camera (201, see FIG. 2).

[0047] For example, the heater body lower surface (312) may be a lower face formed on the heater body (310). The heater body lower surface (312) may face at least one of the battery cell (20, see FIG. 2) and the carrier (100, see FIG. 2).

[0048] The core heater unit (301) may include a heater opening (320). The heater opening (320) may be an opening formed in the heater body (310). The heater opening (320) may be located below the core camera (201, see FIG. 2).

[0049] The field of view (FOV) of the core camera (201, see Fig. 2) can reach the battery cell (20, see Fig. 2) through the heater opening (320). As a result, the core camera (201, see Fig. 2) can photograph the battery cell (20, see Fig. 2).

[0050] The core heater unit (301) may include a heater module (330). The heater module (330) may be connected or coupled to the heater body (310). For example, the heater module (330) may be connected or coupled to the heater body lower surface (312).

[0051] The heater module (330) may include at least one heating segment (335). The heating segment (335) may generate heat. For example, the heating segment (335) may include a laser diode.

[0052] For example, the heating segment (335) can emit infrared rays of a specific wavelength range. For example, the heating segment (335) can emit long wave infrared (LWIR). For example, the heating segment (335) can emit infrared rays of a wavelength of 8 μm to 14 μm.

[0053] For example, a plurality of heating segments (335) may be positioned between sides of the heater body (310) and the heater opening (320). For example, a plurality of heating segments (335) may be positioned along the perimeter of the heater opening (320). A plurality of heating segments (335) may be positioned along an edge of the heater body lower surface (312).

[0054] Referring to FIGS. 3 and 5, the heater module (330) may be provided in multiples. For example, the heater unit (300) may include multiple heater modules (330). For example, the heater unit (300) may include an outer heater module (330t) and an inner heater module (330i). The heater module (330) may include or refer to at least one of the outer heater module (330t) and the inner heater module (330i).

[0055] The inner heater module (330i) may be arranged along the perimeter of the heater opening (320). For example, a plurality of heating segments (335) included in the inner heater module (330i) may be arranged along the perimeter of the heater opening (320).

[0056] The outer heater module (330t) can form a shape that surrounds the inner heater module (330i). For example, the outer heater module (330t) can be placed between the corner of the heater body (310) and the inner heater module (330i). The outer heater module (330t) can be spaced apart from the inner heater module (330i). The outer heater module (330t) can be spaced apart from the corner of the heater body (310).

[0057] The heater module (330) may form a ring shape overall. For example, the heater module (330) may form a square ring shape. For example, the heater module (330) may form a square ring shape with rounded corners.

[0058] Figure 6 is a drawing showing a core heater unit including a plurality of heater modules.

[0059] Referring to FIG. 6, the heater unit (300) may include a plurality of heater modules (330). For example, the heater unit (300) may include a first heater module (330a), a second heater module (330b), a third heater module (330c), and a fourth heater module (330d).

[0060] The heater module (330) may include or mean at least one of a first heater module (330a), a second heater module (330b), a third heater module (330c), and a fourth heater module (330d).

[0061] A plurality of heater modules (330) may surround a heater opening (320). For example, a plurality of heater modules (330) may be arranged along the heater opening (320). The heater opening (320) may be formed by a plurality of heater modules (330).

[0062] For example, the heater opening (320) may be a space formed by a plurality of heater modules (330). For example, the heater opening (320) may be a gap formed by a plurality of heater modules (330).

[0063] For example, a plurality of heater modules (330) may be arranged with a heater opening (320) therebetween. For example, the heater opening (320) may be positioned between the first heater module (330a) and the third heater module (330c). For example, the heater opening (320) may be positioned between the second heater module (330b) and the fourth heater module (330d).

[0064] A plurality of heater modules (330) may be arranged sequentially. For example, a plurality of heater modules (330) may be arranged sequentially along the heater opening (320). For example, a first heater module (330a), a second heater module (330b), a third heater module (330c), and a fourth heater module (330d) may be arranged sequentially along the heater opening (320).

[0065] Figure 7 is a drawing showing a core heater unit and a wing heater unit arranged on top of a carrier.

[0066] Referring to FIG. 7, the battery cell inspection device (10) may include a wing heater unit (302). The heater unit (300) may include or mean at least one of a core heater unit (301) and a wing heater unit (302).

[0067] The wing heater unit (302) may be adjacent to the core heater unit (301). For example, the wing heater unit (302) may be adjacent to an edge portion of the core heater unit (301).

[0068] The wing heater unit (302) may include a heater body (310, see FIG. 3). The heater body (310, see FIG. 3) of the wing heater unit (302) may form a plate shape.

[0069] The heater body (310, see FIG. 3) of the wing heater unit (302) can form an inclination or angle with the heater body (310, see FIG. 3) of the core heater unit (301).

[0070] For example, the lower surface of the heater body (310, see FIG. 3) of the wing heater unit (302) and the lower surface of the heater body (310, see FIG. 3) of the core heater unit (301) can form an obtuse angle.

[0071] For example, the heater body (310, see FIG. 3) of the wing heater unit (302) may face downward at an angle. For example, the heater body (310, see FIG. 3) of the wing heater unit (302) may face the side (or thickness surface) of the cell body (21) at an angle.

[0072] The wing heater unit (302) may include a heater module (330, see FIGS. 4 to 6). The heater module (330, see FIGS. 4 to 6) of the wing heater unit (302) may radiate infrared rays toward the upper surface and side surfaces of the cell body (21).

[0073] The battery cell inspection device (10) may include a wing camera (202). The camera unit (200) may include or mean at least one of a core camera (201) and a wing camera (202).

[0074] The wing camera (202) can face the side of the cell body (21). For example, the wing camera (202) can capture the side of the cell body (21). For example, the wing camera (202) can obtain an image of the side of the cell body (21).

[0075] The wing heater units (302) may be provided in multiples. For example, a pair of wing heater units (302) may be provided facing each of a pair of sides of the cell body (21) and radiate infrared rays.

[0076] For example, the core heater unit (301) may be positioned between a pair of wing heater units (302). For example, the core heater unit (301) and the pair of wing heater units (302) may form a concave shape facing downward.

[0077] The wing cameras (202) may be provided in multiples. For example, a pair of wing cameras (202) may be provided facing each of a pair of sides of the cell body (21) to acquire images. For example, the carrier (100) may be positioned between the pair of wing cameras (202).

[0078] FIG. 8 is a block diagram of a battery cell inspection device according to one embodiment of the present disclosure.

[0079] Referring to FIGS. 1 to 8, the battery cell inspection device (10) may include a control unit (410). The control unit (410) may perform operations. The control unit (410) may process signals. For example, the control unit (410) may transmit and receive signals. For example, the control unit (410) may generate signals.

[0080] For example, the control unit (410) may be implemented through at least one of a computer, a processor, a server, a circuit board (CB), and a printed circuit board (PCB).

[0081] The battery cell inspection device (10) may include an input unit (420). The input unit (420) may obtain input from a user or the like. The input unit (420) may generate a first signal (S1) and transmit it to the control unit (410). The first signal (S1) may include information regarding the input obtained by the input unit (420).

[0082] The battery cell inspection device (10) may include a sensor unit (430). The sensor unit (430) may include a position sensor (431). For example, the position sensor (431) may measure the position of the carrier (100).

[0083] For example, the position sensor (431) can measure the position of the battery cell (20) with respect to the carrier (100). For example, the position sensor (431) can measure the position of the heater unit (300) with respect to the carrier (100). For example, the position sensor (431) can measure the position of the camera unit (200) with respect to the carrier (100).

[0084] The position sensor (431) can generate a second signal (S2) and transmit it to the control unit (410). The second signal (S2) can include information about at least one of the position of the battery cell (20) with respect to the carrier (100), the position of the heater unit (300) with respect to the carrier (100), and the position of the camera unit (200) with respect to the carrier (100).

[0085] The sensor unit (430) may include a temperature sensor (432). The temperature sensor (432) may measure the temperature of the battery cell (20). For example, the temperature sensor (432) may measure the temperature of the outer surface of the cell body (21). For example, the temperature sensor (432) may measure the temperature of the outer surface of the cell body (21) in a non-contact manner.

[0086] The temperature sensor (432) can generate a third signal (S3) and transmit it to the control unit (410). The third signal (S3) can include information regarding the temperature of the outer surface of the cell body (21).

[0087] The control unit (410) can generate output signals (S4, S5, S6) based on input signals (S1, S2, S3). The input signals (S1, S2, S3) can include or mean at least one of the first signal (S1), the second signal (S2), and the third signal (S3). The output signals (S4, S5, S6) can include or mean at least one of the fourth signal (S4), the fifth signal (S5), and the sixth signal (S6).

[0088] The control unit (410) can transmit a fourth signal (S4) to the carrier (100). The fourth signal (S4) can include command information regarding the operation of the carrier (100). The carrier (100) can operate according to the fourth signal (S4). For example, the carrier (100) can move or rotate according to the fourth signal (S4).

[0089] The control unit (410) can transmit a fifth signal (S5) to the heater unit (300). The fifth signal (S5) can include command information regarding the operation of the heater unit (300). The heater unit (300) can operate according to the fifth signal (S5).

[0090] For example, depending on the fifth signal (S5), the power of the heater module (330) may vary. Depending on the power of the heater module (330), the intensity of infrared rays emitted from the heater module (330) may vary.

[0091] The control unit (410) can transmit a sixth signal (S6) to the camera unit (200). The sixth signal (S6) can include command information regarding the operation of the camera unit (200). For example, the camera unit (200) can photograph the battery cell (20) according to the sixth signal (S6).

[0092] The camera unit (200) can transmit a seventh signal (S7) to the control unit (410). The seventh signal (S7) can include information about an image acquired by the camera unit (200).

[0093] The control unit (410) can receive the seventh signal (S7) from the camera unit (200). The control unit (410) can determine the status of the battery cell (20) based on the seventh signal (S7).

[0094] FIG. 9 is a flowchart illustrating a battery cell inspection method according to one embodiment of the present disclosure.

[0095] Referring to FIGS. 1 to 9, the battery cell inspection method (S10) may include an alignment step (S100). In this step (S100), a second signal (S2) may be transmitted to the control unit (410).

[0096] In this step (S100), the position of the carrier (100) relative to the heater unit (300) can be aligned. In this step (S100), the position of the camera unit (200) relative to the carrier (100) can be aligned. In this step (S100), the position of the heater unit (300) relative to the camera unit (200) can be aligned.

[0097] The battery cell inspection method (S10) may include a heating step (S200). In this step (S200), the control unit (410) may transmit a fifth signal (S5) to the heater unit (300).

[0098] In this step (S200), the heater unit (300) can operate according to the fifth signal (S5). For example, in this step (S200), the heater unit (300) can irradiate infrared rays to the battery cell (20).

[0099] The battery cell inspection method (S10) may include a temperature measurement step (S300). The temperature measurement step (S300) may be performed in parallel with the heating step (S200). In this step (S300), the temperature sensor (432) may measure the temperature of the battery cell (20).

[0100] For example, in this step (S300), the temperature sensor (432) can measure the temperature of the outer surface of the cell body (21). For example, in this step (S300), the temperature sensor (432) can generate a third signal (S3).

[0101] The battery cell inspection method (S10) may include a step (S400) of comparing a measured temperature with a reference temperature. The measured temperature may be a temperature extracted from a third signal (S3). For example, the measured temperature may be the temperature of the cell body (21) measured by a temperature sensor (432). This step (S400) may be referred to as a "step of determining whether the temperature of the battery cell is an appropriate temperature."

[0102] For example, in this step (S400), the control unit (410) can compare the measured temperature included in the third signal (S3) with the reference temperature. The reference temperature may be higher than room temperature. The reference temperature may be a temperature at which the cell body (21) is relatively easy to measure.

[0103] The control unit (410) may perform a temperature measurement step (S300) if it is determined that the measured temperature is lower than the reference temperature. The control unit (410) may perform an appearance inspection step (S500) if it is determined that the measured temperature is higher than the reference temperature.

[0104] The battery cell inspection method (S10) may include an appearance inspection step (S500). In this step (S500), the camera unit (200) may photograph the battery cell (20). For example, if the control unit (410) determines that the measured temperature is higher than the reference temperature, the control unit (410) may control the camera unit (200) to obtain a seventh signal (S7).

[0105] After the appearance inspection step (S500) is completed, the battery cell inspection method (S10) may be completed.

[0106] The above description is merely an example of applying the principles of the present disclosure, and other configurations may be further included without departing from the scope of the present disclosure.

Claims

1. Carrier forming the upper face; a core camera positioned above the carrier and facing the upper surface of the carrier; and A core heater unit is located between the carrier and the core camera, and includes a heater module that irradiates infrared rays to the carrier. The above core heater unit, forming a heater opening through which the field of view of the above core camera passes; Battery cell inspection device.

2. In paragraph 1, The above core heater unit, Further comprising a heater body positioned between the carrier and the core camera, The above heater opening is, formed on the above heater body, Battery cell inspection device.

3. In paragraph 2, The above heater module, A plurality of heating segments arranged along the heater opening, each of which radiates infrared rays, Battery cell inspection device.

4. In paragraph 3, The above plurality of heating segments are, Sequentially arranged along the above heater openings, Battery cell inspection device.

5. In paragraph 3, The above plurality of heating segments are, forming the shape of at least one ring, Battery cell inspection device.

6. In paragraph 3, The above heater module, An inner heater module arranged along the above heater opening; and Including an outer heater module located between the inner heater module and the side of the heater body. Battery cell inspection device.

7. In paragraph 6, The inner heater module and the outer heater module are, They are spaced apart from each other and each forms a ring shape. Battery cell inspection device.

8. In paragraph 1, The above core heater unit, Each of the heater modules comprises a plurality of heater modules, which are sequentially arranged and spaced apart from each other along the heater opening. Battery cell inspection device.

9. In paragraph 8, Each of the above plurality of heater modules, comprising at least one heating segment that radiates infrared radiation; Battery cell inspection device.

10. In paragraph 1, Further comprising a wing heater unit adjacent to the core heater unit and obliquely facing the carrier, and irradiating infrared rays to the carrier. Battery cell inspection device.

11. In paragraph 10, The above wing heater unit further comprises a pair of wing heater units, The above core heater unit, Located between the above pair of wing heater units, Battery cell inspection device.

12. In paragraph 11, The above pair of wing heater units and the above core heater unit, concave downwards, Battery cell inspection device.

13. In paragraph 11, Further comprising a pair of wing cameras facing the sides of the carrier, The above carrier, Located between the pair of wing cameras above, Battery cell inspection device.

14. In paragraph 1, Input section that obtains input; a control unit connected to the input unit and receiving a first signal from the input unit; and Further comprising a temperature sensor that measures the temperature of the battery cell placed on the upper surface of the carrier and transmits a third signal to the control unit. Battery cell inspection device.

15. In paragraph 14, The third signal above is, Contains temperature information measured by the above temperature sensor, The above control unit, Based on the input signal, the core heater unit and the core camera are controlled, The above input signal is, comprising at least one of the first signal and the third signal, Battery cell inspection device.

16. In paragraph 15, The above control unit, If the temperature of the battery cell is higher than the reference temperature from the third signal, the core camera is controlled to acquire an image of the battery cell. Battery cell inspection device.

17. Heating step for heating the battery cells placed on the carrier; A temperature measurement step for measuring the temperature of the above battery cell; A step of comparing the above measured temperature with the reference temperature; and Comprising a step of inspecting the appearance of the battery cell, How to inspect battery cells.

18. In paragraph 17, The above heating step and the above temperature measuring step, performed in parallel, How to inspect battery cells.

19. In paragraph 18, If the above measured temperature is higher than the reference temperature, the above appearance inspection step is performed, If the above measured temperature is lower than the reference temperature, the temperature measurement step is performed. How to inspect battery cells.

20. In paragraph 18, Prior to the above heating step, comprising a step of aligning the position of the carrier with respect to the heater unit that heats the battery cell; How to inspect battery cells.

Images