Columnar secondary battery

Abstract

The columnar secondary battery comprises a battery cell and a battery controller, and the battery cell is cylindrical and is provided with a positive electrode and a negative electrode; the battery controller is arranged at one end where a positive electrode or a negative electrode of the battery cell is located, the battery controller comprises a circuit board and a positive electrode cap, the circuit board comprises a first surface and a second surface which are opposite to each other, and a circuit component is welded on the second surface; the electrode cap is made of a conductive metal material and is welded on the first surface of the circuit board in a surface mounting manner, and the first surface of the circuit board is provided with an electrode cap bonding pad for welding the electrode cap. The structure of the controller is optimized by welding the electrode caps in a surface mount manner, so that the axial height of the controller is reduced, and the absolute storage energy and volumetric specific energy of the rechargeable battery are further improved.

Description

[0001] This application is a divisional application of the invention patent application with the application date of January 17, 2020, application number 202010056053.0, and invention name “Cylindrical secondary battery and battery controller”. Technical Field

[0002] The invention relates to a columnar battery, and in particular to a columnar lithium-ion secondary battery technology and a battery controller used in the battery. Background Art

[0003] Cylindrical primary batteries standardized by GB / T 8897.2 (IEC 60086-2), such as the popular Chinese specifications of No. 5 and No. 7 batteries, have been widely used in handheld or portable electronic and electrical products. Since primary batteries cannot be reused and have problems such as high battery cost and environmental pollution caused by discarded batteries, the consumer market has an increasing demand for rechargeable battery products that can replace the primary batteries standardized by GB / T 8897.2 (IEC 60086-2).

[0004] With the rapid development of lithium-ion battery charge and discharge control technology, a method is adopted in which a charge and discharge control circuit controls the charge and discharge of lithium-ion batteries, and a DC-DC energy conversion circuit converts the voltage of lithium-ion batteries into the required voltage for voltage-stabilized discharge, thus forming a secondary rechargeable battery compatible with GB / T 8897.2 (IEC 60086-2). This lithium-ion secondary rechargeable battery has many advantages in terms of nominal voltage compatibility, discharge voltage stability, charging rate, weight and volume specific energy, charge and discharge memory effect and tolerance, and cycle life.

[0005] This type of electronically controlled rechargeable battery, which integrates the charging and / or discharging control circuit, DC-DC energy conversion circuit and lithium-ion battery into one package, or encapsulates the charging circuit in a battery charging box and integrates the discharging control circuit, DC-DC energy conversion circuit and lithium-ion battery into one package, has been widely recognized in the battery consumer market and is gradually replacing traditional electrochemical rechargeable batteries such as nickel-metal hydride batteries.

[0006] In the consumer rechargeable battery market, increasing the absolute storage energy and volume energy of rechargeable batteries and reducing the cost of rechargeable battery products have always been the main direction of market demand, the direction of rechargeable battery product technology development, and also the direction of electronically controlled rechargeable battery product technology development.

[0007] The current packaging method of lithium-ion rechargeable batteries basically integrates the discharge control circuit or the charge and discharge control circuit and the DC-DC energy conversion circuit into a controller, and then packages the controller and the lithium-ion battery cell into one body to form a lithium-ion rechargeable battery. The controller is stacked on the positive or negative end of the battery cell, and the total height of the controller and the battery cell constitutes the total height of the battery. Since the total height and diameter of the cylindrical battery are defined by GB / T 8897.2 (IEC 60086-2), in order to increase the volume of the battery cell and thus increase the absolute storage energy of the battery cell, the height of the controller can only be compressed.

[0008] One way to thin the controller is to omit some functional circuits in the controller to simplify the controller structure and reduce the height of the controller. However, this approach will reduce battery functions and potential safety risks, causing battery overheating or even explosion. Integrating various functional circuits into the controller will result in defects such as complex control circuit structure and large controller size. How to reduce the manufacturing cost of the controller as much as possible, reduce the axial height of the controller, and increase the absolute storage energy of the battery cell while ensuring that the control circuit is fully functional is a difficult problem that the industry needs to overcome urgently.

[0009] According to the position of the controller packaged in the battery, the battery can be divided into two types, one with the controller packaged at the positive end of the battery and the other with the controller packaged at the negative end of the battery. The controller packaged at the positive end usually includes a circuit board and a positive electrode end cap, and the controller packaged at the negative end usually includes a circuit board and a negative electrode cap. Both the positive electrode end cap and the negative electrode cap need to be fixed on the circuit board by welding and establish an electrical connection with the circuit board.

[0010] The brim of the positive electrode cap or the negative electrode cap is usually provided with a pin pin, and a pin hole for inserting the pin pin is provided on the circuit board. Pin pads are provided around the pin hole on the back of the circuit board. After the pin pin is inserted into the circuit board, the pin pin is welded to the pin pad on the back of the circuit board through a spot welding process. On the one hand, this structure has low welding efficiency, and it is necessary to insert the electrode cap one by one and spot weld each pin pin one by one, which has high production costs; on the other hand, the electrode cap with a pin pin structure will occupy the space on the back of the circuit board, so that the pin hole and the pin pad position have to be vacated on the back of the circuit board. In addition, in order to avoid short circuits between the pin pin and other components, the pin pad must be kept away from other components at a certain distance, resulting in a serious shortage of space for arranging other components, and some functional components have to be omitted or the components have to be arranged on the front of the circuit board to increase the total axial height of the controller, thereby affecting the battery capacity.

[0011] How to improve welding efficiency, reduce battery costs, and increase the battery's absolute storage energy and volumetric energy ratio are difficult problems that need to be overcome. Summary of the invention

[0012] The purpose of the present disclosure is to provide a battery controller with low cost and small thickness, which can improve the absolute storage energy and volume specific energy of the secondary battery.

[0013] According to one aspect disclosed in the present application, a battery controller is provided, comprising:

[0014] The circuit board comprises: a first surface and a second surface opposite to each other, wherein the second surface is welded with circuit components;

[0015] The electrode cap is made of conductive metal and is welded to the first surface of the circuit board by patch method. The first surface of the circuit board is provided with an electrode cap pad for welding the electrode cap, and the electrode cap pad has a channel.

[0016] Optionally, the number of the channel is one, the electrode cap pad is in the form of a gap ring interrupted by the channel, and the electrode cap at least partially covers the channel and the electrode cap pad.

[0017] Optionally, the channel divides the electrode cap pad into at least two pad partitions, and each pad partition is symmetrically distributed relative to a center.

[0018] Optionally, the channel is S-shaped, and the electrode cap pad is divided by the channel into two pad partitions that are centrally symmetrically distributed.

[0019] Optionally, each of the channels is distributed in a convergent state from the periphery of the circuit board to the center, and the electrode cap covers the channel and the pad partition.

[0020] Optionally, the number of the pad partitions is more than two, each pad partition encloses an annular area concentric with the outer contour of the electrode cap, the pad partition is fan-shaped, and each pad partition is symmetrically distributed with the vertical mid-plane of the circuit board as the symmetry plane.

[0021] Optionally, the electrode cap is a hollow electrode cap with an inner cavity, and comprises: a cylindrical cap body with one end open and a brim arranged around the open end of the cap body, and the open end of the electrode cap faces the circuit board.

[0022] Optionally, the area where the cap body covers the circuit board is the cap body covering area, the area where the brim covers the circuit board is the brim covering area, the outer contour of each of the pad partitions is located within the outer contour of the brim covering area, and the inner contour of at least one of the pad partitions exceeds the brim covering area and extends inward into the cap body covering area.

[0023] Optionally, a glue injection hole and an exhaust overflow hole are provided on the circuit board, the glue injection hole and the exhaust overflow hole are distributed in the cap body covering area, and the inner cavity of the electrode cap is filled with thermal conductive glue through the glue injection hole.

[0024] Optionally, the electrode cap is a solid disc or a solid cylinder.

[0025] Optionally, the channel is a straight channel, the central angles formed between adjacent channels are equal, the pad partitions are evenly and equally distributed on the circuit board, the electrode cap is a positive electrode cap or a negative electrode cap, the channels converge at the center of the circular circuit board, and the extension direction of the channel is consistent with the radius direction of the circuit board, and the pad partitions are fan-shaped.

[0026] Optionally, the battery controller has only one circuit board, and the circuit components are only distributed on the second surface of the circuit board, or are distributed on the second surface of the circuit board and the portion of the first surface of the circuit board covered by the electrode cap.

[0027] Optionally, the battery controller further includes a controller housing having an inner cavity, and the circuit board is accommodated in the inner cavity of the controller housing.

[0028] Optionally, the controller shell includes a controller outer shell made of metal, one end of the controller outer shell has a limit baffle, and the other end is a bottomless tubular opening end, a through hole is opened in the center of the limit baffle, the electrode cap extends out through the through hole of the limit baffle, and a shell soldering pad is provided near the outer edge of the first surface of the circuit board, and the circuit board is welded or crimped to the inner surface of the limit baffle through the shell soldering pad and is electrically connected to the inner surface of the limit baffle.

[0029] Optionally, the controller housing also includes a controller inner housing made of metal material that is coaxial with the controller outer housing and installed on the second surface of the circuit board. The controller inner housing is accommodated in the controller outer housing, and the controller inner housing includes: an annular inner side wall, an inner shell pad is provided near the outer edge of the second surface of the circuit board, the outer shell pad on the first surface of the circuit board is electrically connected to the inner shell pad on the second surface of the circuit board through a circuit board via, and one end of the controller inner housing is welded to the inner shell pad.

[0030] Optionally, the inner shell of the controller also includes a support portion formed at one end of the inner wall and bent toward the central axis of the inner wall, a circular chamfer is formed between the support portion and the inner wall of the inner shell, the circular chamfer constitutes a transition portion, and a gap for accumulated solder is formed between the transition portion and the outer wall and the inner shell pad of the circuit board.

[0031] Optionally, the support portion includes a plurality of limit bend feet formed at one end of the inner wall and distributed circumferentially along the inner wall, the limit bend feet are spaced apart from each other, grooves are formed between adjacent limit bend feet, one end of each limit bend foot away from the inner wall is bent toward the central axis of the inner wall, and the top of each limit bend foot forms a connecting surface that is flat against the inner shell welding pad.

[0032] Optionally, the support portion includes a fixing ring formed at one end of the inner wall and bent and extended toward the center direction of the inner wall, the fixing ring is fixed to the circuit board through the inner shell pad, and a gap is formed between the fixing ring and the controller outer shell.

[0033] Optionally, the controller also includes an internal electrode for connecting the battery cell, the internal electrode is made of conductive metal, the internal electrode includes an internal electrode fixing portion that fixes and electrically connects the circuit board, the internal electrode also includes an internal electrode battery cell welding station that is bent relative to the internal electrode fixing portion and is used to electrically connect the battery cell, and openings are respectively provided at the opposite ends of the controller housing, the electrode cap is exposed to the controller housing through one of the through holes, and the internal electrode battery cell welding station is exposed to the controller housing through the other opening.

[0034] Optionally, only one end of the inner electrode is fixed to the circuit board to form an inner electrode fixing portion, and the other end of the inner electrode is a movable end constituting the inner electrode core welding station, and the movable end is not connected to the circuit board.

[0035] Optionally, the internal electrode cell welding platform is integrally formed with the internal electrode fixing part, the internal electrode fixing part includes an internal electrode positioning foot that can be inserted into and welded on the circuit board, and an internal electrode circuit board welding platform that is flat against the surface of the circuit board, the circuit board is provided with an internal electrode positioning hole for the internal electrode positioning foot to be inserted, and an internal electrode pad for the internal electrode circuit board welding platform to be flat against and welded thereto, the internal electrode pad surrounds the periphery of the internal electrode positioning hole, so that the internal electrode positioning foot of the internal electrode fixing part and the internal electrode circuit board welding platform share the same pad.

[0036] Optionally, the number of the inner electrode positioning pins is two, the inner electrode circuit board welding platform is located between the two inner electrode positioning pins, and the inner electrode circuit board welding platform is provided with a slot-shaped through hole penetrating the inner electrode circuit board welding platform in the thickness direction thereof.

[0037] Optionally, the inner electrode positioning hole passes through the first surface and the second surface of the circuit board, and the inner electrode positioning hole is exposed on the electrode cap and the controller housing, and the battery controller also includes an electrode cap insulating sheet sleeved on the electrode cap, a through hole is provided in the center of the electrode cap insulating sheet, the electrode cap is exposed outside the electrode cap insulating sheet through the through hole, and the electrode cap insulating sheet covers the inner electrode positioning hole.

[0038] Optionally, the inner electrode core welding platform is formed by integrally extending the inner electrode fixing portion, bending once and then bending twice in the opposite direction, wherein the first bending forms a first contact piece, and the second bending forms a second contact piece, and the second contact piece overlaps with the first contact piece.

[0039] Optionally, the inner electrode core welding platform is formed by integrally extending the inner electrode fixing portion and then bending it once.

[0040] Optionally, the inner cavity of the controller housing is filled with thermally conductive adhesive, the inner electrode core welding platform is exposed outside the thermally conductive adhesive, the thermally conductive adhesive submerges the circuit components on the second surface of the circuit board, and at least a portion of the inner electrode core welding platform is exposed by the controller housing.

[0041] Optionally, the surface of the thermally conductive adhesive is covered with an internal electrode insulating sheet of insulating material, the internal electrode battery core welding station is located outside the internal electrode insulating sheet, the internal electrode battery core welding station is provided with a resistance welding choke groove that runs through its own thickness direction, and the internal electrode insulating sheet is provided with an avoidance groove corresponding to the internal electrode fixing portion.

[0042] According to another aspect disclosed in the present application, there is provided a cylindrical secondary battery, comprising:

[0043] A battery cell, in a cylindrical shape, having a positive electrode and a negative electrode; and,

[0044] A battery controller is coaxially stacked on the positive electrode terminal or the negative electrode terminal of the battery cell and packaged as a whole with the battery cell.

[0045] Optionally, the battery controller also includes a controller shell having an inner cavity, the circuit board is accommodated in the inner cavity of the controller shell, the electrode cap is exposed outside the controller shell, and the second surface of the circuit board is also electrically connected to an internal electrode, the internal electrode is a conductive material, and has an internal electrode battery cell welding station exposed from the controller shell, and the internal electrode battery cell welding station welds and electrically connects the positive electrode or negative electrode of the battery cell.

[0046] Optionally, the battery cell is a soft-pack battery cell, the negative electrode provided at one end of the battery cell is a negative electrode sheet, the negative electrode sheet extends from one end to the other end of the battery cell, the battery cell is inserted into a battery outer shell, the negative electrode sheet is welded to the battery outer shell, and the controller shell is connected to the battery outer shell;

[0047] The positive electrode arranged at the other end of the battery cell is a positive electrode sheet, and the positive electrode sheet is connected to the inner electrode battery cell welding station of the battery controller.

[0048] Optionally, the outer shell of the battery cell is a steel shell, the steel shell of the battery cell is the negative electrode of the battery cell, and the controller housing is connected to the steel shell;

[0049] The battery cell has a positive electrode boss, the positive electrode of the battery cell is connected to the positive electrode boss, and the positive electrode boss is connected to the inner electrode battery cell welding station of the battery controller.

[0050] Optionally, the battery cell is a soft-pack battery cell, the positive electrode provided at one end of the battery cell is a positive electrode sheet, the positive electrode sheet extends from one end to the other end of the battery cell, the battery cell is inserted into a battery shell, the positive electrode sheet is welded to the battery shell, and the controller shell is connected to the battery shell;

[0051] The negative electrode arranged at the other end of the battery cell is a negative electrode sheet, and the negative electrode sheet is connected to the inner electrode battery cell welding station of the battery controller.

[0052] Optionally, the outer shell of the battery cell is an aluminum shell, the aluminum shell of the battery cell is the positive electrode of the battery cell, and the controller housing is connected to the aluminum shell;

[0053] One end of the battery cell has a negative electrode boss, the negative electrode of the battery cell is connected to the negative electrode boss, and the negative electrode boss is connected to the inner electrode battery cell welding station of the battery controller.

[0054] The cylindrical secondary battery and battery controller technical effects of this application are as follows:

[0055] By using PCB board patch and hot air reflow soldering process to fix the positive electrode cap, and using the single-end connection of the inner electrode to the circuit board, the space of the circuit board is saved, so that the circuit components can be distributed on a single side of the circuit board, thereby reducing the overall height of the charge and discharge controller, making more space for the battery cell and increasing the battery cell capacity, thereby improving the volume energy ratio of the rechargeable battery.

[0056] The cooperation between the controller outer shell and the controller inner shell improves the structural strength of the charge and discharge controller and also improves the overall electromagnetic shielding effect of the controller.

[0057] By using PCB board patch and hot air reflow soldering process to install and fix the positive electrode cap, designing electronic components on a single side of the circuit board, using a single-end internal electrode to connect the circuit board and folding the structure and process design at a later stage, the structure and manufacturing process of the charge and discharge controller are simplified, and the material cost and manufacturing cost of the charge and discharge controller are reduced.

[0058] The packaging method of injecting thermal conductive glue into the controller improves the heat dissipation rate of the circuit board control circuit, reduces the temperature difference between the inside and outside of the controller, improves the charging and discharging temperature control accuracy, improves the structural strength of the controller, realizes the structural sealing of the controller, and improves the adaptability and reliability of the charging and discharging working environment of the secondary battery.

[0059] The positive electrode cap is installed and fixed using PCB board patch and hot air reflow soldering process, and the circuit components are designed on a single side of the circuit board, which makes it easier to achieve thick film of the circuit board, thereby simplifying the manufacturing process and reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 is an appearance diagram of a cylindrical secondary battery shown in Example 1;

[0061] Figure 2 This is a diagram showing the assembly state of the battery controller and the steel shell battery cell of Example 1;

[0062] Figure 3 An exploded view of the battery controller of Example 1;

[0063] Figure 4 This is a diagram showing the assembly state of the positive electrode end cap and the circuit board in the battery controller of Example 1;

[0064] Figure 4a This is a first surface view of the circuit board in the battery controller of Example 1;

[0065] Figure 5 This is a diagram showing the assembly state of the inner electrode and the circuit board in the battery controller of Example 1;

[0066] Figure 6 This is a diagram showing the assembly state of the circuit board and the controller housing in the battery controller of Example 1;

[0067] Figure 7 This is a diagram showing the assembly state of the battery controller inner housing and the controller outer housing of Example 1;

[0068] Figure 8 This is a diagram of the battery controller of Example 1 in a state where no glue is injected;

[0069] Fig. 9 This is a state diagram of the battery controller after glue injection in Example 1;

[0070] Fig.10 This is a diagram showing the assembly state of the inner electrode insulating sheet of the battery controller of Example 1;

[0071] Fig.11 The figure is a structural diagram of the inner electrode working state of the battery controller of Example 1;

[0072] Fig.12 This is a diagram showing the assembly state of the electrode cap insulating sheet of the battery controller of Example 1;

[0073] Fig.13 is a cross-sectional view of the battery controller of Example 1 cut along the central axis direction;

[0074] Fig.14 This is a diagram showing the assembly state of the controller and the battery cell of the cylindrical secondary battery shown in Example 2;

[0075] Fig.15 An exploded view of the battery of Example 2;

[0076] Fig.16 An exploded view of the battery controller of Example 2;

[0077] Fig.17 This is a diagram showing the assembly state of the inner electrode and the circuit board in the battery controller of Example 2;

[0078] Fig.18 This is a diagram showing the assembly state of the inner electrode insulating sheet of the battery controller of Example 2;

[0079] Fig.19 This is a working state diagram of the controller of Example 2 after the inner electrode is bent;

[0080] Fig. 20 It is a cross-sectional view of the battery controller of Example 2 cut along the central axis direction;

[0081] Fig.21 This is a diagram showing the assembly state of the controller and the battery cell of the cylindrical battery shown in Example 3;

[0082] Fig. 22 An exploded view of the battery controller of Example 3;

[0083] Fig.23 This is a diagram showing the assembly state of the positive electrode cap and the circuit board in the battery controller of Example 3;

[0084] Fig.24 The structure of the first surface of the circuit board in the battery controller of Example 3;

[0085] Fig.25 This is a diagram showing the assembly state of the inner electrode and the circuit board in the battery controller of Example 3;

[0086] Fig.26This is a state diagram of the battery controller after glue injection in Example 3;

[0087] Fig. 27 This is a structural diagram of the inner electrode working state of the battery controller of Example 3;

[0088] Fig.28 This is a diagram showing the assembly state of the controller and the battery cell of the cylindrical secondary battery shown in Example 4;

[0089] Fig.29 This is a diagram showing the assembly state of the inner electrodes in the battery controller of Example 4;

[0090] Fig.30 This is a state diagram of the battery controller after glue injection in Example 4;

[0091] Fig.31 This is a structural diagram of the inner electrode working state of the battery controller of Example 4;

[0092] Fig.32 is an appearance diagram of a cylindrical secondary battery shown in Example 5;

[0093] Fig.33 An exploded view of the battery controller of Example 5;

[0094] Fig.34 This is a diagram showing the assembly state of the negative electrode cap and the circuit board in the battery controller of Example 5;

[0095] Fig.35 is a cross-sectional view of the battery controller of Example 5 cut along the central axis direction;

[0096] Fig.36 is an appearance diagram of a cylindrical secondary battery shown in Example 6;

[0097] Fig.37 It is a cross-sectional view of the battery controller of Example 6 cut along the central axis direction;

[0098] Fig.38 is a diagram showing the assembly state of the cylindrical secondary battery shown in Example 7;

[0099] Fig.39 This is a welding diagram of the controller circuit board and the electrode cap of Example 7;

[0100] Fig.40 FIG. 1 is a diagram showing the assembly state of the positive electrode cap and the circuit board of Example 7;

[0101] Fig.41 is a cross-sectional view of the battery controller of Example 7 cut along the central axis direction;

[0102] Fig.42 is an appearance diagram of a cylindrical secondary battery shown in Example 8;

[0103] Fig.43 This is a welding diagram of the controller circuit board and the electrode cap of Example 8;

[0104] Fig.44 This is a diagram showing the assembly status of the negative electrode cap and the circuit board of Example 8.

[0105] The following are the descriptions of the reference numerals:

[0106] Batteries 100a, 100b, 100c, 100d, 100e, 100g, 100h;

[0107] Battery cells 200a, 200b, 200c, 200d, 200e, 200g, 200h;

[0108] Cell positive electrodes 230a, 230b, 230c, 230d, 230e;

[0109] Cell negative electrodes 220a, 220b, 220c;

[0110] Battery cell insulation sheets 233a, 233g;

[0111] Circuit boards 300a, 300b, 300c, 300d, 300e, 300f, 300g, 300h; glue injection holes 301a, 301c;

[0112] Exhaust overflow holes 302a, 302c;

[0113] Inner electrode positioning holes 303a, 303c;

[0114] Electrode cap pads 310a, 310c, 310e, 310f, 310g, 310h;

[0115] Pad partitions 311a, 311c, 311e, 311g, 311h;

[0116] Internal electrode pads 312a, 312c;

[0117] Shell pad 313a;

[0118] Inner shell welding pads 314a, 314c;

[0119] Channels 316a, 316c, 316e, 316g, 316h;

[0120] Cap body coverage area outer contour 318a;

[0121] The outer contour of the brim coverage area 317a;

[0122] Positive electrode caps 320a, 320b, 320c, 320e, 323g, 320h;

[0123] Negative electrode caps 320e, 320h;

[0124] Cap body 321a, 321e;

[0125] Brims 322a, 322e;

[0126] Inner electrodes 330a, 330b, 330c, 330d, 330e, 330f, 330g;

[0127] Inner electrode fixing parts 331a, 331b, 331c, 331d, 331e;

[0128] Bending positioning groove 332a;

[0129] Inner electrode positioning pins 3311a, 3311c;

[0130] Inner electrode circuit board welding station 3312a;

[0131] Opening slot 3313c;

[0132] Resistance welding choke groove 333a;

[0133] Inner electrode core welding stations 334a, 334b, 334c, 334e;

[0134] Positioning foot support 335a;

[0135] Controllers 400a, 400b, 400c, 400d, 400d, 400g;

[0136] Controller housings 410a, 410b, 410c, 410d, 410e, 410f, 410g;

[0137] Outer side wall 411a;

[0138] Limit baffles 412a, 412b;

[0139] Inner positioning ring 413a

[0140] Through hole 4112a;

[0141] Controller inner housing 420a, 420b, 420c, 420d, 420e, 420f, 420g;

[0142] Inner wall 421a;

[0143] Outer positioning ring 423b;

[0144] Support portion 422a;

[0145] Limiting bent leg 4221a;

[0146] Groove 4222a;

[0147] transition portion 4422a;

[0148] Thermally conductive adhesive 430a, 430b;

[0149] Inner electrode insulating sheets 440a, 440b, 440c, 440d, 440e, 440f, 440g;

[0150] Electrode cap insulating sheets 450a, 450b, 450c, 450e, 450f, 450g; DETAILED DESCRIPTION

[0151] Although the present invention can be easily embodied in different forms of embodiments, only some of the specific embodiments are shown in the drawings and will be described in detail in this specification. It should be understood that this description should be regarded as an exemplary illustration of the principles of the present disclosure and is not intended to limit the present invention to that described herein.

[0152] Thus, a feature indicated in this specification will be used to illustrate one of the features of an embodiment of the present disclosure, rather than implying that each embodiment of the present invention must have the described feature. In addition, it should be noted that this specification describes many features. Although some features can be combined together to illustrate possible system designs, these features can also be used in other combinations that are not explicitly described. Thus, unless otherwise stated, the described combinations are not intended to be limiting.

[0153] In the embodiments shown in the drawings, the indications of directions (such as up, down, left, right, front and back) used to explain the structure and movement of various elements of the present invention are not absolute but relative. These descriptions are appropriate when these elements are in the positions shown in the drawings. If the description of the positions of these elements changes, the indications of these directions also change accordingly.

[0154] In the present invention, a plurality refers to more than two, and both above and below include the number itself.

[0155] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the examples set forth herein; rather, these example embodiments are provided so that the description of the present disclosure will be more comprehensive and complete and the concepts of the example embodiments will be fully conveyed to those skilled in the art. The accompanying drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and thus their repeated description will be omitted.

[0156] Before introducing the various embodiments of the present application, an overview of some battery names, technical terms and battery classifications that appear in the present application is given.

[0157] For the convenience of description, this application divides batteries into two categories: N-type batteries and P-type batteries according to the system integration mode of the controller used in the lithium-ion cylindrical secondary battery (Note: N-type batteries and P-type batteries are abbreviations created by this application for the convenience of description).

[0158] N-type battery, that is, the battery controller is installed at the positive electrode end of the battery. The battery shell is the negative electrode for battery charging input and discharge output; the positive electrode cap is the positive electrode for battery charging input and discharge output.

[0159] P-type battery, that is, the battery controller is installed at the negative electrode end of the battery. The battery shell is the positive electrode for battery charging input and discharge output; the negative electrode cap is the negative electrode for battery charging input and discharge output.

[0160] The No. 5 and No. 7 batteries mentioned in this application are the common specifications in China. The comparison table with other specifications is as follows:

[0161] GB / IEC Standards American Popular Specifications Chinese popular specifications Nominal voltage R6 AA No. 5 1.5V R03 AAA No.7 1.5V

[0162] The batteries described in this application that have built-in charging and discharging protection circuits and have commodity attributes are called "batteries", and batteries that do not have built-in charging and discharging protection circuits and are industrial semi-finished products are called "battery cells".

[0163] In the description of the embodiment, the battery is divided into "steel shell lithium ion battery", "soft package lithium ion battery", "aluminum shell lithium ion battery" and the like according to the packaging method of the battery cell, wherein:

[0164] Soft-pack lithium-ion battery cell: a reference term derived from the lithium-ion battery industry's well-known abbreviation for a single lithium-ion battery that is packaged in aluminum-plastic film and does not have a built-in charge and discharge protection circuit.

[0165] Steel shell lithium-ion battery cell: a reference term, derived from the lithium-ion battery industry's well-known abbreviation for a single lithium-ion battery that is encapsulated in a metal steel shell and does not have a built-in charge and discharge protection circuit.

[0166] Aluminum shell lithium ion battery cell: This is a proprietary abbreviation created by the present application for the convenience of presentation. It refers to a single lithium ion battery that is packaged in a metal aluminum shell and does not have a built-in charge and discharge protection circuit.

[0167] Statement on the positive and negative electrodes of the battery cell:

[0168] In the lithium-ion battery industry, the sheet-shaped lead-out electrode welded to the anode or cathode current collector of the lithium-ion battery core is generally called a "pole ear". Even if the pole ear has been led to the outside of the battery cell package, or even has been transferred to other materials, as long as the electrode is still a sheet structure, it is still habitually called a "pole ear", such as the positive pole ear and negative pole ear of the soft-pack lithium-ion battery cell; but for steel-shell or steel-shell lithium-ion batteries, generally only the electrode led out of the core is called a "pole ear", and the electrode led out of the battery cell package is called the positive electrode and the negative electrode because it is no longer in sheet form;

[0169] In order to facilitate understanding with well-known professional concepts and to facilitate the description of implementation methods, in this application, the lithium-ion battery core lead-out electrodes, soft-pack lithium-ion battery cell lead-out electrodes, steel-shell lithium-ion battery cell lead-out electrodes, and aluminum-shell lithium-ion battery cell lead-out electrodes are all collectively referred to as "positive electrodes" or "negative electrodes" according to their electrical polarities.

[0170] The preferred embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings of this specification.

[0171] Embodiment 1, N-type No. 5 steel shell lithium ion secondary battery.

[0172] See also Figure 1 and Figure 2 The battery 100a mainly includes: a battery cell 200a and a controller 400a. The battery cell 200a is cylindrical and has a battery cell positive electrode 230a and a battery cell negative electrode 220a. The controller 400a is coaxially stacked at the end where the battery cell positive electrode 230a is located and is packaged as a whole with the No. 5 steel shell battery cell 200a.

[0173] The battery cell 200a shown in this embodiment is a CID battery cell, that is, a battery cell with a current cut-off protection structure. When the battery cell fails (such as overheating, short circuit, overcharging, etc.), a lot of gas will be generated inside. When the pressure increases, the battery cell will automatically break the circuit and play a protective role.

[0174] The outer shell of the battery cell 200a is a steel shell, and the internal structure of the battery cell is not the main technical problem to be solved by the present invention, so the description is omitted.

[0175] A positive electrode boss electrically connected to the positive electrode 230a is formed at the positive electrode 230a of the No. 5 steel shell battery cell, and a battery cell insulating sheet 233a is sleeved on the positive electrode boss. A through hole is provided at the center of the battery cell insulating sheet 233a, and the through hole cooperates with the positive electrode boss to position the battery cell insulating sheet 233a with the positive electrode boss as the center, and is pasted on the outer shell of the battery cell 200a. When the controller 400a is welded to the battery cell 200a, the battery cell insulating sheet 233a serves to isolate the battery cell positive electrode 230a and the controller shell. The technical problems mainly solved by the present invention are basically developed around the controller 400a part, which will be described in detail below through the accompanying drawings.

[0176] See also Figure 3 , Figure 4 and Figure 4a The controller 400a of this embodiment mainly includes a circuit board 300a and a positive electrode cap 320a disposed on the circuit board 300a.

[0177] The circuit board 300a has a first surface and a second surface opposite to each other. The positive electrode cap 320a is disposed on the first surface of the circuit board 300a. Various circuit components for realizing the controller function are disposed on the second surface of the circuit board 300a.

[0178] The positive electrode cap 320a is soldered to the first surface of the circuit board by patch method. The first surface of the circuit board 300a is provided with an electrode cap pad 310a for soldering the positive electrode cap 320a. The circuit board 300a has a plurality of channels 316a, and the channels 316a separate the electrode cap pad into a plurality of pad partitions 311a. The channel 316a here refers to a non-welding structure that cannot be used for welding. The simplest way to form a channel is to arrange pad partitions spaced apart from each other on the circuit board, and the intervals between each pad partition constitute the channel 316a. Insulating solder mask ink or other insulating material layers can also be applied at the intervals to form a channel. Optionally, the surface of the channel is lower than the height of the surface of the pad partition 311a, or the two can be of the same height.

[0179] The electrode cap pad 310a is electrically connected to the charging input terminal and the discharging output terminal of the control circuit of the circuit board 300a. After the positive electrode cap 320a is welded and fixed to the electrode cap pad 310a of the circuit board 300a and electrically connected, the positive electrode cap 320a becomes the positive electrode of the charging input and discharging output of the secondary battery.

[0180] Compared with the traditional method of providing pins on the electrode cap, inserting the pins into the circuit board and welding them to the circuit board, the positive electrode cap patch method of the present application can free up space on the second surface of the circuit board for arranging pins, so that more circuit components can be arranged on the second surface of the circuit board, so that the circuit components can be arranged only on the second surface of the circuit board, truly realizing the single-sided arrangement of circuit components on the circuit board, greatly reducing the overall height of the controller, and freeing up space for the battery cells.

[0181] In addition, the electrode cap pad is designed as a partition structure, and a channel 316a is formed between adjacent pads. Therefore, when the positive electrode cap is placed on the electrode cap pad in the form of a patch and passes through the reflow soldering machine, the gas volatilized by the flux in the solder paste can diffuse out through the channel 316a. If the electrode cap pad is set as a non-partitioned structure without a channel, when the flux of the solder paste on the pad volatilizes, it is easy to push the positive electrode cap 320a open, causing the positive electrode cap 320a to be skewed. At the same time, compared with a whole non-partitioned pad, during the soldering process of the circuit board passing through the reflow soldering machine, the partition structure of the pad can disperse the stress on the surface of the solder paste, and release the stress through the channel 316a, so that the stress of the surface of the melted solder paste on each pad partition 311a is controlled within a certain range, which can effectively suppress the drift of the positive electrode cap when the circuit board and the positive electrode cap 320a pass through the reflow soldering machine. If the solder paste is not applied evenly, the excess solder paste on the pad can be discharged to the isolation groove. Therefore, the pad partition structure can ensure that the positive electrode cap mounted by PCB board patch is flat and not skewed.

[0182] The positive electrode cap 320a is made of nickel-plated iron stamping or other conductive metal materials, so that the positive electrode cap 320a can be welded to the electrode cap pad 310a using PCB board patch and hot air reflow soldering process, and the electrode cap pad 310a can participate in shielding the electromagnetic radiation generated by the control circuit of the circuit board 300a, and conduct the heat generated by the control circuit of the circuit board 300a to the outside of the controller. The positive electrode cap 320a is made of nickel-plated iron stamping or other conductive metal materials, and the structural strength and oxidation resistance of the positive electrode cap 320a can also meet the structural technical conditions of the positive electrode for charging input and discharging output of the rechargeable battery.

[0183] Optionally, the number of channels 316a is preferably more than three, and the channels 316a divide the electrode cap pad 310a into multiple pad partitions 311a, and each pad partition 311a is symmetrically distributed relative to a center, so that the positive electrode cap 320a will be automatically positioned to the center during reflow soldering to avoid reflow soldering deviation.

[0184] In this embodiment, each channel 316a is a straight channel, and is distributed in a convergent state from the periphery to the center of the circuit board 300a. When designing the channel 316a, the virtual center of the channel convergence can be located at the preset position of the center of the positive electrode cap 320a, so that when the positive electrode cap 320a passes through the reflow soldering machine, the channel 316a has a centering effect on the center of the positive electrode cap 320a, so that the center of the positive electrode cap 320a is automatically guided to the preset position, ensuring that the positive electrode cap 320a is accurately positioned on the circuit board 300a, and avoiding reflow soldering deviation.

[0185] The positive electrode cap 320a of this embodiment is a hollow electrode cap with an inner cavity, which includes: a cylindrical cap body 321a with an opening at one end and a brim 322a arranged around the opening end of the cylindrical cap body. The cap body 321a includes a cylindrical cap wall and a cap top closed at one end of the cap wall, and the brim 322a is perpendicular to the cap wall of the cap body 321a. The positive electrode cap 320a is buckled on the circuit board 300a with its opening end facing the circuit board 300a, and is welded to the circuit board 300a through the brim 322a. When the positive electrode cap 320a is welded to the circuit board 300a, the brim 322a of the positive electrode cap 320a covers each pad partition 311a and each channel 316a. Each pad partition 311a is distributed into an annular area, the center of which is concentric with the annular brim 322a of the positive electrode cap 320a, so that when passing through the reflow soldering machine, each pad partition 311a and the brim of the positive electrode cap 320a have a centering effect to ensure that the positive electrode cap 320a does not drift.

[0186] When the circuit has many functions and it is impossible to implement single-sided layout of circuit components on the second surface of the circuit board, the circuit components can also be arranged in the inner cavity of the positive electrode cap 320a, thereby controlling the overall height of the controller within an extremely low range and making room for the battery cells.

[0187] Optionally, the brim 322a is not of equal size to the electrode cap pad on the circuit board 300a. The area where the cap body 321a covers the circuit board is the cap body covering area (318a in the figure is the outer contour of the cap body covering area), and the area where the brim covers the circuit board is the brim covering area (317a in the figure is the outer contour of the brim covering area). There is a pad blank area in the cap body covering area 318a, and the outer contour of each pad partition 311a is located within the outer contour 317a of the brim covering area, that is, the outer diameter of the pad partition 311a is smaller than the diameter of the outer contour 317a of the brim covering area. This structure can further suppress the drift of the positive electrode cap 320a when the circuit board 300a and the positive electrode cap 320a pass through the reflow soldering machine. The inner contour of at least one pad partition 311a exceeds the brim covering area and extends inward into the cap body covering area, that is, enters into the outer contour 318a of the cap body covering area. Therefore, when the circuit board 300a and the positive electrode cap 320a pass through the reflow soldering machine, the molten solder paste can climb upward along the cap wall of the positive electrode cap 320a, thereby increasing the welding strength between the positive electrode cap 320a and the circuit board 300a.

[0188] In this embodiment, the circuit board 300a is circular, the positive electrode cap brim 322a is an annular brim, the electrode cap pad is an annular pad, and the pad is partitioned into a sector shape. Therefore, from the figure, the outer diameter of the electrode cap pad annular structure is smaller than the outer diameter of the positive electrode cap brim 322a, and the inner diameter of the electrode cap pad annular structure is smaller than the inner diameter of the positive electrode cap brim 322a.

[0189] Optionally, the central angles formed between adjacent channels 316a are equal, that is, the central angles of each fan-shaped pad partition 311a are equal, so that each channel 316a is evenly distributed on the circuit board, so that the gas volatilized from the flux in the solder paste during reflow soldering can be evenly diffused through the evenly distributed channels 316a, preventing the positive electrode cap from drifting.

[0190] Optionally, each pad is evenly and equally distributed on the circuit board, so that the stress on the solder paste surface of the electrode cap pad is more uniform, thereby preventing the electrode cap from tilting.

[0191] The vertical mid-plane of the circuit board is defined as a vertical plane passing through the center of the circuit board and perpendicular to the circuit board. Optionally, the pad partitions 311a of this embodiment are symmetrically distributed with the vertical mid-plane of the circuit board as the symmetry plane, which is conducive to uniform distribution of solder paste stress on the surface of each pad partition 311a and improves the concentricity and coaxiality of the positive electrode cap and the circuit board 300a.

[0192] The circuit board 300a is also provided with a glue injection hole 301a and an exhaust overflow hole 302a, which are distributed within the outer contour 318a of the cap body covering area of ​​the positive electrode cap 320a, so that the inner cavity of the positive electrode cap 320a can be filled with thermal conductive glue through the glue injection hole 301a to improve the heat dissipation performance of the circuit board 300a. The exhaust overflow hole 302a is used to exhaust gas during the thermal conductive glue pouring process, and after the cavity formed by the first surface of the circuit board 300a and the positive electrode cap 320a is filled with thermal conductive glue, overflow to the second surface of the circuit board 300a. In addition, before glue injection, when the positive electrode cap 320a is reflow soldered, due to the increase in temperature, the gas in the cavity formed by the positive electrode cap 320a and the first surface of the circuit board 300a expands due to the heat. At this time, the expanded gas can be discharged through the glue injection hole 301a and the exhaust overflow hole 302a to balance the air pressure inside and outside the cavity formed by the positive electrode cap 320a and the first surface of the circuit board 300a, so as to avoid the positive electrode cap 320a being tilted by the expanded gas when the circuit board 300a and the positive electrode cap 320a pass through the reflow soldering machine.

[0193] See also Figure 3-Figure 8 The controller 400a also includes a controller housing having an inner cavity, and the circuit board is accommodated in the inner cavity of the controller housing.

[0194] Optionally, in this embodiment, the controller housing includes a controller housing 410a. The controller housing 410a is made of iron stamping and then nickel-plated, and can also be made of other conductive metal materials.

[0195] One end of the controller housing 410a has a limit baffle 412a, and the other end is a bottomless tubular opening end. The controller housing 410a includes: a cylindrical outer wall 411a and a limit baffle 412a integrally formed at one axial end of the outer wall 411a. A through hole 4112a is provided in the center of the limit baffle 412a, and a shell pad 313a for welding the limit baffle 412a is provided near the outer edge of the first surface of the circuit board 300a. The circuit board 300a is accommodated in the controller housing 410a, and by applying solder paste to the shell pad 313a, the circuit board 300a is attached and fixed to the inner surface of the limit baffle 412a of the controller housing 410a, and is electrically connected to the limit baffle 412a. At this time, the positive electrode cap 320a extends out through the through hole 4112a of the limit baffle 412a. The shell solder pad 313a not only fixes the controller shell 410a, but also establishes an electrical connection between the controller shell 410a and the circuit board 300a through solder paste welding, so that the shell solder pad 313a and the controller shell 410a together participate in shielding the electromagnetic radiation generated by the controller 400a.

[0196] In this embodiment, the housing pad 313a is an annular pad, which is beneficial to increase the contact area of ​​the electrical connection between the circuit board 300a and the controller housing 410a, and is beneficial to pass a large current and improve the heat dissipation efficiency of the circuit board 300a. In other embodiments, it can also be a plurality of pads distributed near the outer edge of the first surface of the circuit board 300a.

[0197] Optionally, the controller housing further includes a controller inner housing 420a disposed in the controller outer housing 410a.

[0198] The controller inner housing 420a is made of iron by stamping and then nickel-plating, and can also be made of other conductive metal materials.

[0199] The controller inner shell 420a is coaxially installed in the controller outer shell 410a. The controller inner shell 420a includes: an annular inner side wall 421a coaxial with the outer side wall 411a of the controller outer shell 410a, and an inner shell pad 314a for welding the controller inner shell 420a to the second surface of the circuit board 300a is provided near the outer edge of the second surface of the circuit board 300a. The outer shell pad 313a on the first surface of the circuit board 300a and the inner shell pad 314a on the second surface of the circuit board 300a are electrically connected through the circuit board via. During installation, solder paste can be applied on the inner shell pad 314a of the circuit board 300a, and then the controller inner shell 420a can be installed so that one end of the controller inner shell 420a is against the inner shell pad 314a of the circuit board 300a. The circuit board 300a, the controller inner shell 420a, and the controller outer shell 410a can be connected and fixed by directly heating the controller outer shell 410a to melt tin and weld.

[0200] In this embodiment, the inner shell pad 314a is an annular pad. In other embodiments, it may be a plurality of pads distributed on the second surface of the circuit board 300a near the outer edge.

[0201] On the one hand, the controller inner shell 420a can increase the connection strength between the circuit board 300a and the controller outer shell 410a. On the other hand, it can also increase the electromagnetic shielding effect of the controller and increase the electrical contact area between the circuit board 300a and the controller shell, which is conducive to the passage of large current and improves the heat dissipation efficiency of the circuit board 300a.

[0202] Optionally, see Figure 7 and Fig.13 The controller inner housing 420a further includes a support portion 442a formed at one end of the inner side wall 421a and bent toward the central axis of the inner side wall 421a. The other end of the controller inner housing 420a opposite to the support portion 442a is a bottomless tubular opening end. A circular chamfer is formed between the support portion 442a and the inner side wall 421a of the controller inner housing, and the circular chamfer forms a transition portion 4422a. A gap for accumulating solder is formed between the transition portion 4422a and the outer side wall 411a and the inner housing pad 314a of the circuit board 300a.

[0203] When the controller inner shell 420a is inserted into the controller outer shell 410a, the support portion 442a of the controller inner shell 420a squeezes the solder paste on the inner shell pad 314a of the circuit board 300a, and squeezes the solder paste into the gap formed between the controller inner shell 420a, the outer wall 411a of the controller outer shell and the circuit board 300a, and accumulates the solder paste in the gap, thereby firmly welding the circuit board 300a, the controller inner shell 420a and the controller outer shell 410a.

[0204] Specifically, the support portion 422a includes: a plurality of limiting bend feet 4221a formed at one end of the inner wall 421a and distributed circumferentially along the inner wall 421a, the limiting bend feet 4221a are spaced apart from each other, and grooves 4222a are formed between adjacent limiting bend feet 4221a, and one end of the limiting bend foot 4221a away from the inner wall is bent toward the central axis direction of the inner wall to form an arc chamfer, and the top of each limiting bend foot 4221a forms a connecting surface that is flat against the inner shell welding pad 314a.

[0205] When the controller inner shell 420a is clamped in the controller outer shell 410a, the connection surface at the top of each limit bent leg 4221a will squeeze the solder paste on the inner shell pad 314a of the circuit board 300a, so that the solder paste enters the gap formed between the outer side of the arc chamfer of the limit bent leg 4221a of the controller inner shell 420a, the outer side wall 411a of the controller outer shell, and the circuit board 300a. In addition, the solder paste will also be squeezed into the gap of the groove 4222a between the adjacent controller inner shell welding feet. Therefore, the circuit board 300a, the controller inner shell 420a, and the controller outer shell 410a can be firmly welded.

[0206] In addition, the diameter of the circuit board 300a is slightly smaller than the inner cavity diameter of the controller outer shell 410a, and an inter-board gap is formed between the outer periphery of the circuit board 300a and the outer side wall 411a of the controller outer shell 410a. The excess solder paste between the first surface of the circuit board 300a and the limit baffle 412a of the controller outer shell 410a will also be squeezed into the inter-board gap, and fused and bonded with the solder paste on the second surface of the circuit board and the solder paste accumulated in the above-mentioned gap to form a strong bonding group, so as to further improve the connection strength among the circuit board 300a, the controller inner shell 420a, and the controller outer shell 410a.

[0207] In other embodiments, there may be no groove 4222a between the above-mentioned limit bend legs 4221a, so that each limit bend leg 4221a is connected to each other to form a fixed ring, that is, the above-mentioned support portion 422a is replaced by: a fixing ring formed at one end of the inner wall and bent and extended toward the center direction of the inner wall, the bending portion of the fixing ring forms an arc chamfer, the fixing ring is fixed to the circuit board 300a through the inner shell solder pad 314a, and the circuit board 300a, the controller inner shell 420a, and the controller outer shell 410a are firmly connected by accumulating solder paste through the gap formed between the arc chamfer of the fixing ring and the outer wall 411a of the controller outer shell 410a.

[0208] In other embodiments, tin wire or tin ball may be used instead of tin paste, and the gap or groove may be filled with fluid tin solder after the tin wire or tin ball is melted.

[0209] The controller housing of this embodiment adopts the method of clamping and fixing the two sides of the circuit board 300a by the controller inner housing 420a and the controller outer housing 410a, so as to firmly fix the circuit board 300a and prevent the circuit board from collapsing due to the action of falling or dropping during the use of the battery. At the same time, since the controller inner housing 420a is annular in structure as a whole, it only serves to fix and connect the circuit board around the circuit board 300a, and does not occupy the space of the circuit components in the middle part of the circuit board, so as to ensure that the circuit components are arranged on one side of the circuit board, and control the overall height of the controller within the lowest possible height range. In addition, the double-layer shell structure of the inner and outer shells can also significantly improve the overall anti-electromagnetic shielding effect of the controller, increase the electrical contact area between the circuit board 300a and the controller housing, facilitate the passage of large current, and improve the heat dissipation efficiency of the circuit board 300a.

[0210] See also Fig.13 The controller outer shell 410a extends downward beyond the controller inner shell 420a, thereby forming an inner positioning ring 413a. When the controller 400a is fixed to the battery cell 200a, the battery cell outer shell extends into the inner positioning ring 413a. The inner positioning ring 413a is used to abut against the outer shell of the battery cell 200 to ensure that the controller 400a is installed concentrically and coaxially with the battery cell 200a.

[0211] It should be noted that when the controller inner shell 420a and the controller outer shell 410a cooperate to fix the circuit board 300a, the circuit board 300a and the limit baffle 412a of the controller outer shell 410a do not need to be welded. Instead, by welding between the controller inner shell 420a and the inner shell solder pad 314a of the circuit board 300a and by welding between the controller inner shell 420a and the controller outer shell 410a, the shell solder pad 313a on the first surface of the circuit board 300a is pressed against the inner surface of the limit baffle 412a, thereby realizing that the circuit board 300a is crimped to the limit baffle 412a of the controller outer shell 410a and establishing an electrical connection between the two.

[0212] See also Figure 3 and Figure 5-Figure 11 , the circuit board 300a is also provided with an inner electrode 330a, and the inner electrode 330a is made of a conductive metal material. One end of the inner electrode 330a is fixed and electrically connected to the circuit board 300a, forming an inner electrode fixing portion 331a. The inner electrode 330a also includes an inner electrode cell welding platform 334a formed by bending relative to the inner electrode fixing portion 331a for electrically connecting the cell 200a. A space for arranging circuit components is formed between the bent inner electrode cell welding platform 334a and the circuit board 300a. The inner electrode cell welding platform 334a is exposed to the controller housing through the opening end at the bottom of the inner and outer housings of the controller.

[0213] The inner electrode 330a of this embodiment is a single-pin structure, that is, only one end of the inner electrode 330a is fixed to the circuit board to form a single fixed end, and the other end of the inner electrode 330a is a movable end that is not connected to the circuit board 300a. The movable end of the single-pin inner electrode 330a is not connected to the circuit board 300a, so a large space can be freed up, so that more functional components can be arranged on the second surface of the circuit board 300a.

[0214] In other embodiments, if the controller has simple functions and fewer circuit components, or the diameter of the circuit board 300a is larger due to the battery model, the inner electrode 330a can also be designed to have double fixed feet, that is, an inner electrode fixing portion 331a is designed at each end of the inner electrode cell welding platform 334a, so that both ends of the inner electrode cell welding platform 334a become fixed ends.

[0215] Specifically, the internal electrode core welding platform 334a and the internal electrode fixing part 331a of this embodiment are an integrally formed structure. The internal electrode fixing part 331a includes an internal electrode positioning foot 3311a that can be inserted and welded on the circuit board 300a and an internal electrode circuit board welding platform 3312a flatly attached to the surface of the circuit board. The circuit board 300a is provided with an internal electrode positioning hole 303a for the internal electrode positioning foot 3311a to be inserted and an internal electrode pad 312a for the internal electrode circuit board welding platform 3312a to be flatly attached thereto and welded thereto. The internal electrode pad 312a surrounds the periphery of the internal electrode positioning hole 303a, and the internal electrode positioning foot 3311a of the internal electrode fixing part and the internal electrode circuit board welding platform 3312a share the same internal electrode pad 312a. The internal electrode positioning foot 3311a is used to participate in the tin melting welding, thereby reducing the current density at the welding connection and ensuring the welding position accuracy of the internal electrode 330a and the circuit board 300a.

[0216] The inner electrode pad 312a is used as a pad for welding the inner electrode 330a, and is also a pad for connecting the positive electrode 230a of the cell of the control circuit on the circuit board 300a. After the inner electrode 330a is fixedly welded and electrically connected to the inner electrode pad 312a of the circuit board 300a, the inner electrode 330a becomes a structural electrode for connecting the positive electrode of the cell 200a to the control circuit of the circuit board.

[0217] When welding the inner electrode 330a, its inner electrode positioning foot 3311a is inserted into the inner electrode positioning hole 303a to realize the positioning of the inner electrode 330a and the circuit board 330a. In addition, since the inner electrode positioning hole 303a passes through the first surface and the second surface of the circuit board, and the inner electrode positioning hole 303a is exposed to the positive electrode cap 320a and the limit baffle 412a of the controller housing, when the rechargeable battery is assembled, the inner electrode positioning hole 303a can also be used as a battery cell test hole, and a pointed test lead is inserted into the inner electrode positioning hole 303a on the first surface of the circuit board, that is, in contact with the inner electrode 330a. In this way, the positive electrode of the battery cell 200a can be directly electrically connected across the controller 400a to detect the battery cell.

[0218] After the inner electrode 330a is bent and formed, the inner electrode fixing portion 331a further includes a positioning foot support portion 335a. There are two inner electrode positioning feet 3311a, which are respectively arranged at positions close to both sides of the width direction of one end of the positioning foot support portion 335a and are integrally extended from the positioning foot support portion 335a. The inner electrode circuit board welding platform 3312a is a welding piece integrally extended and bent from the positioning foot support portion 335a. The inner electrode circuit board welding platform 3312a is located between the two inner electrode positioning feet 3311a. The inner electrode circuit board welding platform 3312a is provided with a slot-shaped through hole that runs through its thickness direction. During welding, solder paste is placed in the slot-shaped through hole. When the inner electrode circuit board welding platform 3312a is heated by a soldering iron or other welding tools, the solder paste melts and extends along the hole wall of the slot-shaped through hole, thereby fixing the inner electrode circuit board welding platform 3312a to the circuit board 300a. At the same time, the inner electrode circuit board welding platform 3312a also increases the contact area between the inner electrode 330a and the circuit board 300a, which is conducive to the passage of large current and improves the heat dissipation efficiency of the control circuit.

[0219] In addition, the inner electrode positioning foot 3311a of the inner electrode 330a is inserted into the inner electrode positioning hole 303a of the circuit board 300a, so that the inner electrode 330a and the circuit board 300a are positioned in the xy direction, and the inner electrode circuit board welding platform 3312a is against the inner electrode pad 312a on the second surface of the circuit board 300a, so that the inner electrode 330a and the circuit board 300a are positioned in the Z direction. At the same time, the inner electrode circuit board welding platform 3312a also increases the contact area between the inner electrode 330a and the circuit board 300a, which is conducive to passing a larger current and reducing the heat generated at the connection part between the inner electrode 330a and the circuit board 300a.

[0220] See also Figure 2 and Figure 5 When the controller 400a is assembled on the positive terminal of the battery cell 200a, the inner electrode battery cell welding platform 334a of the inner electrode 330a just falls on the positive electrode 230a boss of the battery cell, and the two can be welded to establish an electrical connection between the two.

[0221] The inner electrode cell welding platform 334a is also provided with a resistance welding choke groove 333a to increase the current path passing through when the inner electrode cell welding platform 334a is resistance welded with the cell positive electrode boss, thereby increasing the welding strength.

[0222] Since the battery cell 200a of this embodiment is a steel shell battery cell, its positive electrode 230a is a boss structure. In order to facilitate welding the inner electrode battery cell welding platform 334a to the battery cell 200a, the inner electrode battery cell welding platform 334a of this embodiment adopts a two-bend structure.

[0223] See also Fig.10 and Fig.11 The internal electrode cell welding platform 334a is formed by an integral extension of the internal electrode fixing portion 331a, after being bent once and then bent twice in the opposite direction. The first bending forms a first contact piece, and the second bending forms a second contact piece. The second contact piece overlaps with the first contact piece, and the internal electrode cell welding platform 334a is formed at the end of the second contact piece.

[0224] A bending positioning groove 332a is respectively provided on both sides of the inner electrode cell welding platform 334a in the width direction. When the inner electrode cell welding platform 334a is bent, stress is concentrated at the two bending positioning grooves 332a, which can ensure that the inner electrode cell welding platform 334a is folded at the bending positioning grooves, thereby realizing secondary bending positioning with the connecting line of the two bending positioning grooves 332a as the folding line, thereby ensuring the consistency of the inner electrode folding.

[0225] The movable end of the inner electrode 330a of this embodiment is in the shape of a long strip. Since the battery of this embodiment is a No. 5 battery, its diameter is larger than that of a No. 7 battery, and therefore, the diameter of the circuit board is relatively large, so a wider inner electrode 330a and an inner electrode cell welding platform 334a can be designed, so that the width of the movable end of the long strip inner electrode 330a can meet the requirements of welding with the positive electrode boss of the cell. Using the movable end of the long strip inner electrode 330a can save materials, simplify the manufacturing process, and reduce process costs.

[0226] See Figure Figure 8-Figure 11The inner cavity of the controller housing is filled with thermally conductive adhesive 430a made of insulating material. When pouring thermal conductive glue, the controller is placed in a vacuum environment with the positive electrode cap facing downward, and the pre-prepared thermal conductive glue is poured into the controller through the glue injection hole 301a of the circuit board 300a. After the thermal conductive glue 430a fills the inner cavity formed by the first surface of the circuit board 300a and the positive electrode cap 320a, it overflows from the exhaust overflow hole 302a to the inner cavity formed by the second surface of the circuit board 300a and the controller outer shell 410a. After continuous pouring until the glue plane reaches a position that submerges the circuit components on the second surface of the circuit board 300a, the controller is taken out. The cured thermal conductive glue 430a can protect the circuit components in the controller on the one hand, and on the other hand, it serves as the main heat conduction medium for conducting the heat generated by the control circuit in the controller to the controller outer shell 410a and the positive electrode cap 320a, so as to improve the heat dissipation efficiency of the controller, reduce the temperature difference between the inside and outside of the controller, improve the charging or discharging temperature control accuracy of the controller, improve the structural strength of the controller, realize the structural sealing of the controller, and improve the adaptability and reliability of the battery charging and discharging working environment.

[0227] The thermal conductive adhesive 430a is a thermosetting colloid, which can be prepared by mixing dicyandiamide into epoxy resin to modify it into a single-component thermosetting colloid, and then mixing it with thermal conductive powder materials such as aluminum nitride or boron nitride to modify it into a thermal conductive colloid.

[0228] In other embodiments, the thermal conductive adhesive 430a may also be made of other colloids such as thermosetting benzoxazine, mixed with other thermal conductive powder materials such as aluminum nitride or boron nitride to be modified into a thermal conductive adhesive.

[0229] The pouring process of the thermal conductive adhesive 430a can also be achieved by pouring the thermal conductive adhesive in a normal pressure environment, and then placing it in a vacuum oven to heat, remove bubbles, and level it.

[0230] The inner electrode cell welding platform 334a is exposed outside the thermal conductive adhesive 430a, and the movable end of the inner electrode cell welding platform 334a is exposed by the opening at the bottom of the controller housing, so as to facilitate the electrical connection of the battery cell 200a. The surface of the thermal conductive adhesive 430a is also covered with an inner electrode insulating sheet 440a made of insulating material. The inner electrode cell welding platform 334a is located outside the inner electrode insulating sheet 440a, and the inner electrode insulating sheet 440a is provided with an avoidance groove corresponding to the inner electrode fixing portion 331a. The inner electrode insulating sheet 440a prevents the inner electrode cell welding platform 334a from being short-circuited by contact with the electronic components on the circuit board 300a after being bent. In addition, the cured thermal conductive adhesive 430a can also provide positioning for the inner electrode cell welding platform 334a, so that the inner electrode cell welding platform 334a in the suspended state is blocked by the thermal conductive adhesive 430a and the battery cell 200a on both sides of the axial direction of the controller, so that it can be kept as relatively stable as possible in the use state.

[0231] During implementation, the thermal conductive adhesive 430a can be poured into the controller first. At this time, the thermal conductive adhesive 430a is in a gel state with a smooth surface. The inner electrode insulating sheet 440a is placed on the gel-state adhesive plane to ensure the flatness of the inner electrode insulating sheet 440a. Then the entire controller is placed in an oven to heat and cure the thermal conductive adhesive. The cured thermal conductive adhesive 430a is tightly adhered to the inner electrode insulating sheet 440a to form a whole with the overall controller.

[0232] The inner electrode insulating sheet 440a can be made of insulating materials such as highland barley paper, ABS, PC, and PET.

[0233] In other embodiments, the inner electrode insulating sheet 440a may also be manufactured as a structure with adhesive backing, and then mounted on the thermal conductive adhesive 430a after the thermal conductive adhesive is cured.

[0234] See also Fig.12 The controller also includes an electrode cap insulating sheet 450a sleeved on the positive electrode cap 320a, a through hole is set in the center of the electrode cap insulating sheet 450a, the positive electrode cap 320a is exposed outside the electrode cap insulating sheet 450a through the through hole, the electrode cap insulating sheet 450a covers the brim 322a of the positive electrode cap 320a and the outer surface of the limiting baffle 412a of the controller outer shell, and covers the inner electrode positioning hole 303a on the first surface of the circuit board for inserting and connecting the inner electrode 330a.

[0235] The electrode cap insulating sheet 450a can be made of insulating materials such as PC, PET, ABS, etc., and can have adhesive backing, so that it can be pasted on the brim 322a of the positive electrode cap 320a and the outer surface of the limit baffle 412a of the controller outer shell to ensure insulation between the positive electrode cap 320a and the controller shell.

[0236] Figures 4 to 12FIG. 1 is an assembly sequence diagram of the controller 400a. When assembling the controller 400a, firstly, various circuit components are welded on the second surface of the circuit board, and then the positive electrode cap 320 is soldered to the first surface of the circuit board, and then the inner electrode 330a is inserted into the inner electrode positioning foot 3311a of the circuit board 300a, and one end of the inner electrode 330a is soldered to the circuit board 300a. Then, the circuit board 300a is placed into the inner cavity of the controller outer shell 410a from the open end of the controller outer shell 410a, so that the circuit board 300a is close to the limit baffle 412a of the controller outer shell 410a, and the circuit board is soldered to the limit baffle 412a through the outer shell pad 313a on the first surface of the circuit board 300a, and then the controller inner shell 420a is installed into the controller outer shell 410a, so that the limit bending foot 4221a of the controller inner shell 420a is against the periphery of the second surface of the circuit board, and the controller is heated, and the outer shell pad 313a on the first surface of the circuit board 300a is used to heat the controller. The solder paste pre-coated on the inner shell pad 314a on the second surface 13a is melted to fix the circuit board 300a, the controller outer shell 410a and the controller inner shell 420a together, and then the open end of the controller is facing upward, and the thermal conductive glue 430a is poured into the inner cavity of the controller, and then the inner electrode insulating sheet 440a is placed, and then the inner electrode 330a is bent from the part where the thermal conductive glue 430a is submerged, and the part submerged by the thermal conductive glue 430a is the inner electrode fixing foot 331a The active end of the part not submerged by the thermal conductive adhesive forms an internal electrode cell welding platform 334a, and the internal electrode cell welding platform 334a is bent reversely again to form a folded state when the internal electrode 330a is working; thereafter, the electrode cap insulating sheet 450a is passed through the cap body of the positive electrode cap 320a and is placed on the surface of the limit baffle 412a and the positive electrode cap brim 322a of the controller outer shell 410a, and is bonded and connected to the limit baffle 412a and the positive electrode cap brim 322a.

[0237] See also Figure 1 When the controller 400a is assembled in the battery cell 200a, the controller outer shell 410a of the controller shell is connected to the steel shell on the outer surface of the battery cell. The steel shell of the battery cell 200a is the negative electrode of the battery cell 200a, and the positive electrode boss is connected to the internal electrode battery cell welding station 331a of the battery controller.

[0238] The technical effects of the N-type No. 5 steel shell lithium-ion secondary battery of this embodiment are as follows:

[0239] (1) Reduce the height of the charge and discharge controller and improve the specific energy of the rechargeable battery.

[0240] By using PCB board patch and hot air reflow soldering process to weld and fix the positive electrode cap, and using the method of connecting the inner electrode to the circuit board at a single end, the space of the circuit board can be saved, so that the circuit components can be distributed on a single side of the circuit board, thereby reducing the overall height of the charge and discharge controller, making more space for the steel shell lithium-ion battery cell with CID and increasing the battery cell capacity, thereby improving the volume energy ratio of the rechargeable battery.

[0241] (2) The coordination between the controller outer shell and the controller inner shell improves the structural strength of the charge and discharge controller.

[0242] The circuit board is mounted between the controller outer shell and the controller inner shell, and the controller inner shell has a supporting structure, which improves the overall structural strength of the controller and the overall electromagnetic shielding effect of the controller.

[0243] (3) Simplify the charge and discharge controller structure and process to reduce the cost of rechargeable batteries.

[0244] By using PCB board patch and hot air reflow soldering process to install and fix the positive electrode cap, designing electronic components on a single side of the circuit board, using a single-end internal electrode to connect the circuit board and folding the structure and process design at a later stage, the structure and manufacturing process of the charge and discharge controller are simplified, and the material cost and manufacturing cost of the charge and discharge controller are reduced.

[0245] (4) Improve the adaptability and reliability of secondary battery charging and discharging.

[0246] The packaging method of injecting thermal conductive glue into the controller improves the heat dissipation rate of the circuit board control circuit, reduces the temperature difference between the inside and outside of the controller, improves the charging and discharging temperature control accuracy, improves the structural strength of the controller, realizes the structural sealing of the controller, and improves the adaptability and reliability of the charging and discharging working environment of the secondary battery.

[0247] (5) It is easier to achieve thicker film on circuit boards.

[0248] The positive electrode cap is installed and fixed using PCB board patch and hot air reflow soldering process, and the circuit components are designed on a single side of the circuit board, which makes it easier to achieve thick film of the circuit board, thereby simplifying the manufacturing process and reducing costs.

[0249] Embodiment 2, N-type AA soft-pack lithium-ion secondary battery.

[0250] Figures 14 to 20 This is a structural diagram of an N-type AA soft-pack lithium-ion secondary battery and its controller.

[0251] See also Fig.14 and Fig.15 The battery 100b includes a battery outer shell 110b, a battery cell 200b and a controller 400b.

[0252] The battery cell 200b of this embodiment is a soft-pack lithium-ion battery cell. Like the above embodiment, it is also cylindrical and has a battery cell positive electrode 230b and a battery cell negative electrode 220b.

[0253] The battery outer shell 110b is a cylindrical structure with one end open and the other end closed. The battery cell positive electrode 230b is a positive electrode sheet, and the battery cell negative electrode 220b is a negative electrode sheet.

[0254] The positive electrode 230b of the battery cell is a tab structure with a certain length. After the negative electrode 220b of the battery cell is extended, it is bent toward the end where the positive electrode of the battery cell 220b is located, close to the shape of the battery cell.

[0255] The battery controller is coaxially stacked at the end where the positive electrode 230b of the battery cell is located, and the battery cell 220b and the controller 400b are packaged as a whole through the battery outer shell 110b.

[0256] During assembly, the battery cell 220b is first inserted into the battery outer shell 110b with the negative electrode 220b of the battery cell facing the closed end of the battery outer shell 110b. The negative electrode 220b of the battery cell is welded and fixed to the battery outer shell 110b at the open end of the battery outer shell 110b by conventional resistance welding or laser welding methods to establish electrical connection, and then the inner electrode battery cell welding platform 334a of the inner electrode 330b of the controller 400b is overlapped and welded with the positive electrode 230b of the battery cell, and finally the housing of the controller 400b is welded to the open end of the battery outer shell 110b, thus achieving battery packaging.

[0257] The design method adopted by the controller of the secondary battery composed of the soft-pack lithium-ion battery in this embodiment is basically the same as that of the controller of the secondary battery composed of the steel-shell lithium-ion battery in the above-mentioned embodiment 1. The difference in the design method caused by the difference in technical requirements is mainly that: the controller inner shell 420b of the controller 400b of the soft-pack lithium-ion battery in this embodiment and the controller outer shell 410b form an outer positioning ring 423b so as to be assembled and positioned with the battery outer shell 110b; the inner electrode 330b is short and is only bent once.

[0258] The following will be combined Figures 16 to 20 The differences between the controller 400 b of this embodiment and the controller 400 a of the first embodiment 1 are described in detail.

[0259] Similar to the above-mentioned embodiment 1, the controller 400b of this embodiment also includes a controller outer shell 410b, a controller inner shell 420b, a circuit board 300b, a positive electrode cap 320b, an inner electrode 330b, an inner electrode insulating sheet 440b and an electrode cap insulating sheet 450b.

[0260] As in the first embodiment, the inner electrode 330b of this embodiment also includes an inner electrode fixing portion 331b and an inner electrode core welding platform 334b. The structure of the inner electrode fixing portion 331b is the same as that of the first embodiment, and will not be described here. The inner electrode core welding platform 334b ​​is shorter than that of the first embodiment, and is bent only once. That is, the inner electrode core welding platform is formed by extending the inner electrode fixing portion 331b in one piece and then bending once.

[0261] See also Fig. 20 In this embodiment, the controller inner shell 420b is not retracted into the controller outer shell 410b, but extends outward from the controller outer shell 410b, thereby forming an outer positioning ring 423b. When the controller 400b is fixed to the battery cell 200b, the outer positioning ring 423b can extend into the battery outer shell 110b and abut against the battery outer shell 110b, ensuring that the controller 400b is installed concentrically and coaxially with the battery cell 200b and the battery outer shell. In addition, during the welding process of the controller outer shell 410b and the battery outer shell 110b, the outer positioning ring 423b also prevents welding flames or welding slag from entering the battery outer shell 110b to damage the lithium-ion battery cell.

[0262] When assembling the inner electrode 330b, first press the inner electrode 330b Fig.17 As shown in the figure, the circuit board 300b is welded and mounted on the controller outer shell 410b, and the controller inner shell 420b is installed, and then the circuit board is welded and mounted on the controller outer shell 410b. Fig.18 As shown in FIG. 1 , the thermal conductive glue 440b is poured and the inner electrode insulating sheet 440b is placed, and then the Fig.19 As shown, the inner electrode 330b is bent from the place where the thermal conductive glue 430b is submerged, and then, Fig. 20 As shown, the electrode cap insulating sheet 450b is placed through the cap body of the positive electrode cap 320b on the surface of the limiting baffle 412b and the positive electrode cap brim 322b of the controller outer shell 410b, and is bonded to the limiting baffle 412b and the positive electrode cap brim 322b.

[0263] Compared with the first embodiment, the inner electrode 330 b of the present embodiment is shorter and only needs to be bent once, thereby reducing the structural materials of the rechargeable battery, simplifying the manufacturing method, and reducing the process cost.

[0264] Embodiment 3, N-type No. 7 steel shell lithium ion secondary battery.

[0265] Figure 21 to Figure 27 The figure is a structural diagram of an N-type No. 7 steel-shell lithium-ion secondary battery and its controller.

[0266] The secondary battery structure of this embodiment is similar to that of embodiment 1, except that embodiment 1 is a No. 5 battery, while this embodiment is a No. 7 battery. Since the diameter of the No. 7 battery is smaller than that of the No. 5 battery, there will be slight differences in the controller design, which are mainly manifested in: the movable end of the inner electrode 330c of the controller 400c of the No. 7 steel shell lithium-ion secondary battery of this embodiment is circular, and the electrode cap pad 310c has a different shape.

[0267] See also Fig.21 The battery 100c includes: a battery cell 200c and a controller 400c.

[0268] The battery cell 200c of this embodiment is a steel-shell lithium-ion battery cell, which is also cylindrical and has a battery cell positive electrode 230c and a battery cell negative electrode 220c as in the above embodiment 1. The controller 400c is disposed at the end where the battery cell positive electrode 230c is located.

[0269] See also Fig. 22 As in the above-mentioned embodiment 1, the controller 400c of this embodiment also includes a controller outer shell 410c, a controller inner shell 420c, a circuit board 300c, a positive electrode cap 320c, an inner electrode 330c, an inner electrode insulating sheet 440c and an electrode cap insulating sheet 450c.

[0270] See also Fig.23 and Fig.24 Since the diameter of the No. 7 battery in this embodiment is smaller, the diameter of the controller 400c is also smaller, and correspondingly the diameter of the circuit board 300c is also smaller. The diameters of some vias on the circuit board 300c that connect the first surface and the second surface of the circuit board are also smaller. In order to avoid the holes being blocked by solder paste during the process of applying solder paste before reflow soldering, it is best to design the solder pads to avoid the holes as much as possible.

[0271] The electrode cap pad 310c of the present embodiment is also divided into a plurality of pad partitions 311c by each channel 316c. Each pad partition 311c is an asymmetric structure. At each via hole, each pad partition 311c is designed with a corresponding avoidance structure. Each pad partition 311c is also designed with an avoidance structure near the injection hole 301 and the exhaust overflow hole 302c, so that each pad partition 311c presents an irregular structure as a whole.

[0272] However, since the electrode cap pad 310c of the present embodiment is also divided into a partitioned structure by a plurality of channels 316c, when the positive electrode cap is placed on the electrode cap pad in the form of a patch and passes through a reflow soldering machine, the gas volatilized from the flux in the solder paste can diffuse out through the channel 316c, and the partitioned structure of the pad can disperse the stress on the surface of the solder paste and release the stress through the channel 316c, so that the surface stress of the molten solder paste on each pad partition 311c is controlled within a certain range, which can effectively suppress the drift of the positive electrode cap when the circuit board 300c and the positive electrode cap 320c pass through the reflow soldering machine, thereby ensuring that the positive electrode cap mounted on the PCB board in the form of a patch is flat and not skewed.

[0273] See also Figure 25 to Figure 27 , which is an assembly sequence diagram of the internal electrode 330c of this embodiment. The internal electrode 330c of this embodiment is similar to the internal electrode 330a in Example 1, both of which have two bending structures. The difference is that the movable end of the internal electrode core welding platform 334c of this embodiment is circular, and the shape of the internal electrode circuit board welding platform 3312c of the internal electrode fixing part 331c is also different.

[0274] The inner electrode 330c of this embodiment also includes an inner electrode fixing portion 331c and an inner electrode cell welding platform 334c. The inner electrode cell welding platform 334c is a two-way bending structure to facilitate connection with the boss-shaped steel shell cell positive electrode 230c. The movable end of the inner electrode cell welding platform 334c is circular, the purpose of which is to increase the area of ​​the movable end of the inner electrode cell welding platform 334c, thereby facilitating welding with the positive electrode boss of the cell 200c and increasing the contact area between the movable end of the inner electrode cell welding platform 334c and the positive electrode boss of the cell 200c.

[0275] The inner electrode fixing portion 331c includes: two inner electrode positioning pins 3311c and an inner electrode circuit board welding platform 3312c located between the two inner electrode positioning pins 3311c and parallel to the circuit board 300c. The inner electrode circuit board welding platform 3312c is bent into an L shape, and the end of the inner electrode circuit board welding platform 3312c is in a fork shape. An opening groove 3313c is formed on the edge of the inner electrode circuit board welding platform 3312c, and two conductive flanges are formed on both sides of the opening groove 3313c. The lengths of the two conductive flanges are different. The inner electrode positioning pin 3311c is the same as the above-mentioned embodiment 1 and embodiment 2, and will not be repeated here.

[0276] The circuit board 300c is provided with an inner electrode pad 312c for welding the inner electrode 330c, and an inner electrode positioning hole 303C is provided in the inner electrode pad 312c. The inner electrode positioning foot 3311c of the inner electrode 330c is inserted into the inner electrode positioning hole 303C, and is fixed and electrically connected with the inner electrode pad 312c by solder, and the inner electrode circuit board welding platform 3312c is flatly attached to the inner electrode pad 312c and is fixed and electrically connected with the inner electrode pad 312c by solder. During welding, since the inner electrode circuit board welding platform 3312c is in a fork-shaped shape, the solder will extend along the opening groove 3313c and the periphery of the two conductive flanges, thereby enhancing the connection strength between the inner electrode 330c and the circuit board 300c. At the same time, the inner electrode circuit board welding platform 3312c also increases the contact area between the inner electrode 330c and the circuit board 300c, which is conducive to the passage of large current and improves the heat dissipation efficiency of the control circuit.

[0277] In addition, the second surface of the circuit board 300c of the present embodiment is used to weld the inner shell pads 314c of the controller inner shell 420C, which are multiple and have an irregular structure and are arranged at intervals at the circumferential edge of the circuit board 300c, so that more space can be freed up on the second surface of the circuit board to arrange circuit components, thereby realizing single-sided arrangement of circuit components on a circuit board with a smaller diameter, thereby reducing the overall axial height of the controller.

[0278] Embodiment 4, N-type AAA soft-pack lithium-ion secondary battery.

[0279] Figure 28 to Figure 31 This is a structural diagram of an N-type AA soft-pack lithium-ion secondary battery and its controller.

[0280] See also Fig.28 The battery 100d includes: a battery cell 200d and a controller 400d.

[0281] The battery cell 200d of this embodiment is a soft-pack lithium-ion battery cell, which is also cylindrical and has a battery cell positive electrode 230d and a battery cell negative electrode as in the above embodiment 2. The controller 400d is arranged at the end where the battery cell positive electrode 230d is located.

[0282] The secondary battery structure of this embodiment is similar to that of embodiment 2, except that embodiment 2 is a No. 5 battery, while this embodiment is a No. 7 battery. Since the diameter of the No. 7 battery is smaller than that of the No. 5 battery, there will be slight differences in the controller design, which is mainly manifested in that the movable end of the inner electrode 330d of the controller 400d of the No. 7 soft-pack lithium-ion secondary battery in this embodiment is circular.

[0283] The inner electrode 330d of this embodiment also includes: an inner electrode fixing portion 331d and an inner electrode battery cell welding station 334d. The structure of the inner electrode fixing portion 331b is the same as that of the above-mentioned embodiment 1, and will not be repeated here. The inner electrode battery cell welding station 334b ​​is shorter than that of the above-mentioned embodiment 1, and is only bent once, which is convenient for lap welding with the long strip battery cell positive electrode 230d of the soft-pack lithium-ion battery cell. And the movable end of the inner electrode 330d is circular, which increases the contact area with the battery cell positive electrode 230d, which is conducive to welding and the passage of large current between the two.

[0284] The structure of the inner electrode fixing portion 331d of the inner electrode 330d of this embodiment is the same as the structure of the inner electrode fixing portion 331c of the above-mentioned embodiment 3, that is, it also includes two inner electrode positioning feet and an inner electrode circuit board welding platform located between the two inner electrode positioning feet. The inner electrode circuit board welding platform is also in a fork shape. The specific structure and technical effects of the inner electrode circuit board welding platform have been described in detail in the above-mentioned embodiment 3 and will not be repeated here.

[0285] Embodiment 5, P-type No. 5 aluminum shell lithium ion secondary battery.

[0286] Figure 32 to Figure 35 The structure diagram of the P-type No. 5 aluminum shell lithium-ion secondary battery and its controller.

[0287] The battery 100e also includes two parts: a battery cell 200e and a controller 400e.

[0288] The battery cell 200e of this embodiment is an aluminum shell lithium ion battery cell, that is, the battery cell is packaged in a metal aluminum shell, and its appearance is similar to that of a steel shell lithium ion battery cell, and is also cylindrical, and has a battery cell positive electrode 230e and a battery cell negative electrode. The aluminum shell of the battery cell 200e is the battery cell positive electrode, and one end of the battery cell 200e has a negative electrode boss, and the negative electrode of the battery cell 200e is connected to the negative electrode boss.

[0289] The biggest difference between this embodiment and the above-mentioned embodiments 1-4 is that the controller 400e of this embodiment is arranged at the end where the negative electrode of the battery cell is located. Accordingly, the positive electrode cap on the first surface of the circuit board in the controller 400e is replaced with a negative electrode cap 320e with a larger diameter. After the battery is assembled, the negative electrode cap 320e is exposed at one end of the battery 100e, and the inner electrode battery cell welding platform of the inner electrode contacts and electrically connects to the negative electrode boss of the battery cell. The controller shell is connected to the aluminum shell of the battery cell, and the other end of the battery 100e opposite to the negative electrode cap 320e is the boss-type positive electrode cap 230e of the battery cell.

[0290] Specifically, see Figure 33 to Figure 35The controller 400e of this embodiment includes: a controller outer shell 410e, a controller inner shell 420e, a circuit board 300e, a negative electrode cap 320e, an inner electrode 330e, an inner electrode insulating sheet 440e and an electrode cap insulating sheet 450e.

[0291] The controller outer shell 410e, the controller inner shell 420e, the inner electrode 330e, the inner electrode insulating sheet 440e and the electrode cap insulating sheet 450e are the same as those in the above-mentioned embodiment 1 and are not described again here.

[0292] The negative electrode cap 320e of this embodiment is also a hollow electrode cap with an inner cavity, including: a cylindrical cap body 321e with an opening at one end and a ring-shaped brim 322e arranged around the opening end of the cylindrical cap body. The cap body 321e includes a cylindrical cap wall and a cap top closed at one end of the cap wall. The brim 322e is perpendicular to the cap wall of the cap body 321e. The negative electrode cap 320e is inverted on the circuit board 300e with its open end facing the circuit board 300e, and is welded to the circuit board 300e through the brim 322e. Compared with the positive electrode cap 320a, the cap body of the negative electrode cap 320e has a larger diameter and the radial dimension of the brim 322e is smaller.

[0293] The circuit board 300e is used to weld the electrode cap pad 310e of the negative electrode cap 320e. The circuit board 300e is also provided with a plurality of channels 316e. Each channel 316e divides the electrode cap pad 310e into a plurality of pad partitions 311e.

[0294] Optionally, there are more than three pad partitions 311e, and in this embodiment, there are 8 pad partitions. Each pad partition 311e encloses an annular area, and when the negative electrode cap 320e is welded to the circuit board 300e, the brim 322e of the negative electrode cap 320e covers each channel 316e and each pad partition 311e. Therefore, when the negative electrode cap 320e is placed on the electrode cap pad 310e in the form of a patch and passes through the reflow soldering machine, the gas volatilized from the flux in the solder paste can diffuse out through the channel 316e, and disperse the stress on the surface of the solder paste, and release the stress through the channel 316e, so that the stress on the surface of the melted solder paste on each pad partition 311e is controlled within a certain range, which can effectively suppress the drift of the positive electrode cap when the circuit board 300e and the positive electrode cap 320e pass through the reflow soldering machine, and ensure that the positive electrode cap mounted in the form of a PCB patch is flat and not skewed.

[0295] The center of the annular area surrounded by each pad partition 311e is concentric with the brim 322e of the negative electrode cap 320e, so that when passing through the reflow soldering machine, each pad partition 311e and the brim of the negative electrode cap 320e have a centering effect to ensure that the negative electrode cap 320e does not drift.

[0296] In this embodiment, when the controller 400e is packaged as one with the battery cell 200e, the inner electrode 330e of the controller 400e contacts and establishes an electrical connection with the negative electrode of the battery cell. At this time, compared with the above-mentioned embodiments 1-4, its control circuit will be changed accordingly. In other embodiments, the controller 400e can also be packaged at the negative electrode end of the battery cell, but insulation is provided between the inner electrode 330e of the controller 400e and the negative electrode of the battery cell, and the inner electrode 330e of the controller 400e is connected to the positive electrode 230e of the battery cell through a wire or a conductive sheet. At this time, the control circuit of the controller 400e can adopt the controller circuit of the above-mentioned embodiments 1-4.

[0297] Example 6, P-type No. 5 soft-pack lithium-ion secondary battery.

[0298] Figure 36 to Figure 37 This is a structural diagram of the controller for a P-type AA soft-pack lithium-ion secondary battery.

[0299] Similar to the P-type No. 5 aluminum shell lithium-ion secondary battery of the fifth embodiment, the controller of the secondary battery of the present embodiment is also packaged at the negative electrode end of the battery cell.

[0300] Different from the above-mentioned Example 5, the battery cell of this embodiment is a soft-pack battery cell, and the positive electrode arranged at one end of the battery cell is a positive electrode sheet, the positive electrode sheet extends from one end to the other end of the battery cell, the battery cell is inserted into a battery outer shell, the positive electrode sheet is welded to the battery outer shell, the controller outer shell is connected to the battery outer shell, and the negative electrode arranged at the other end of the battery cell is a negative electrode sheet, and the negative electrode sheet is connected to the internal electrode battery cell welding station of the controller 400f.

[0301] The controller 400f of this embodiment also includes: a controller outer shell 410f, a controller inner shell 420f, a circuit board 300f, a negative electrode cap 320f, an inner electrode 330f, an inner electrode insulating sheet 440f and an electrode cap insulating sheet 450f.

[0302] Different from the above-mentioned embodiment 5, the inner electrode 330f of the controller of this embodiment is a short structure suitable for soft-pack batteries, and its inner electrode battery welding platform 334f is formed by one bending, so as to match and overlap with the long-ear negative electrode of the soft-pack battery to establish an electrical connection.

[0303] Example 7, N-type No. 5 steel shell lithium ion secondary battery (positive electrode cap is solid).

[0304] Figures 38 to 41 It is a structural diagram of the controller of the N-type No. 5 steel shell lithium-ion secondary battery of this embodiment.

[0305] The secondary battery 100g of this embodiment is similar to the secondary battery 100a of the first embodiment. The controller 400g of this embodiment is also packaged at the positive electrode end of the battery cell 200g. A battery cell insulating sheet 233g is provided between the controller 400g and the battery cell 200g.

[0306] The difference between the secondary battery 100g of this embodiment and the secondary battery 100a of the above-mentioned embodiment 1 is that the positive electrode cap 323g on the controller 400g of this embodiment is a solid structure, and accordingly the shape of the pad on the circuit board 300g for welding the solid positive electrode cap 323g is also slightly different. Other structures, such as: the controller inner shell 420g, the controller outer shell 410g, the inner electrode 330g, the inner electrode insulating sheet 440g and the electrode cap insulating sheet 450g are the same as those in the above-mentioned embodiment 1, so the description of the same structure is omitted in this embodiment.

[0307] The positive electrode cap 323g is a solid disc or a solid cylinder. The first surface of the circuit board 300g is provided with an electrode cap pad 310g for welding the electrode cap 323g. The electrode cap pad 310g is located in the area of ​​the circuit board covered by the solid electrode cap 323g. The first surface of the circuit board 300g is provided with a plurality of channels 316g, each channel 316g divides the electrode cap pad 310g into a plurality of pad partitions 311g. The function of the channel 316g is the same as that of the channel in the above-mentioned embodiment 1, which is used to prevent the positive electrode cap 323g from drifting during reflow soldering.

[0308] In this embodiment, each channel 316g is a straight channel, and is distributed in a convergent state from the periphery of the circuit board 300g to the center. Each channel 316g intersects at the center of the circular circuit board 300g, and the extension direction of the channel 316g is consistent with the radial direction of the circuit board 300g. Thus, the channel 316g forms an automatic centering effect on the positive electrode cap 323g, and the electrode cap 323g is automatically centered on the center of the circuit board 300g.

[0309] The channels 316g of this embodiment converge at the center, so that each pad partition 311g has a fan-shaped structure. In other embodiments, the channels 316g can also be designed as a central intersection structure. For example, the channels 316g in Example 1 are only distributed in a convergent state but do not converge at a center. At this time, each pad partition 311g is distributed into an annular area. This structure can also have a centering effect on the positive electrode cap 323g during reflow soldering, ensuring that the positive electrode cap and the circuit board 300g are concentrically and coaxially welded.

[0310] Optionally, each pad partition 311g is centrally symmetrical with respect to the center of the circuit board, so that the welding stress on the circuit board 300g is more evenly distributed, ensuring the flatness of the circuit board welding.

[0311] Since the solid bottom surface of the solid positive electrode cap 323g of this embodiment can be used as the welding surface of the welding circuit board 300g, the solid positive electrode cap 323g removes the brim structure, and its radial size is smaller, which reduces the area of ​​the first surface of the circuit board 300g occupied by the positive electrode cap 323g, thereby freeing up space on the first surface for arranging other functional circuit components. In addition, the manufacturing process of the solid positive electrode cap 323g is simple, and only one stamping process is required to form it, saving manufacturing costs.

[0312] Example 8, P-type No. 7 aluminum shell lithium-ion secondary battery (negative electrode cap is solid).

[0313] See also Figure 42 to Figure 44 The secondary battery of this embodiment is similar to the secondary battery of the above-mentioned embodiment 7, the difference is that the embodiment 7 is a No. 5 battery, and the present embodiment is a No. 7 battery, which is smaller in size; in addition, the controller 400h of this embodiment is installed at the end where the negative electrode of the battery cell 200h is located, and the electrode cap on the controller 400h is replaced with a solid negative electrode cap 323h. When the controller 400n is welded together with the battery cell 200h, its negative electrode cap 323h is exposed to the outside of the battery, opposite to the positive electrode cap 320h of the positive electrode of the battery cell 200h. The positive electrode cap 320h serves as the charging input and discharging output end of the battery 100h, and the negative electrode cap 323h serves as the charging input and discharging output end of the battery 100h.

[0314] The outer shell of the battery cell 200h is an aluminum shell, the aluminum shell of the battery cell 200h is the positive electrode of the battery cell, the controller shell is connected to the aluminum shell, one end of the battery cell 200h has a negative electrode boss, the negative electrode of the battery cell 200h is connected to the negative electrode boss, and the negative electrode boss is connected to the internal electrode cell welding station of the battery controller 400h.

[0315] The negative electrode cap 323h of this embodiment is a solid structure, and the radial dimension and axial height of the negative electrode cap 323h can be designed as needed to make it a solid disc or a solid cylinder. The circuit board 300h is provided with an electrode cap pad 310h for welding the solid negative electrode cap 323h. Different from the above-mentioned embodiment 7, the electrode cap pad 310h of this embodiment is an asymmetric structure, and each pad partition 311h is provided with an avoidance structure at each via position on the corresponding circuit. The channel 316h of this embodiment is the same as the above-mentioned embodiment 7, and its technical effect also refers to the above-mentioned embodiment 7, which will not be repeated here.

[0316] In other embodiments, there may be only one channel on the circuit board. In this case, the electrode cap pad may be in the form of a notched ring interrupted by the channel. When the electrode cap patch is welded to the circuit board, the electrode cap at least partially covers the channel and the electrode cap pad, that is, the electrode cap has a physical structure covering the channel and the electrode cap pad.

[0317] When the number of channels is one and the channel is a straight channel, the electrode cap pad may also be two opposite and symmetrically distributed semicircles, or two opposite and symmetrically distributed semirings.

[0318] When the number of channels is one, the channel may also be S-shaped. In this case, the electrode cap pad is divided by the channel into two pad partitions that are centrally symmetrically distributed and resemble a Tai Chi figure.

[0319] When there are multiple channels, each channel may converge to a center in a vortex shape, or each channel may be distributed in a vortex-like convergence state but not converge to a center.

[0320] No matter the electrode cap is a positive electrode cap or a negative electrode cap, solid or hollow, all the above electrode cap pad shapes are applicable, and can achieve the effect of dispersing the surface stress of solder paste and diffusing the volatilized gas of flux during electrode cap patch welding, ensuring that the electrode cap is not skewed or drifted during reflow soldering.

[0321] The structural features of the above embodiments can also be cross-applied to batteries of different models and types as needed, and are not limited to the fixed combination structure in the above examples.

[0322] Although the present disclosure has been described with reference to several typical embodiments, it should be understood that the terms used are illustrative and exemplary, rather than restrictive. Since the present invention can be embodied in a variety of forms without departing from the spirit or essence of the invention, it should be understood that the above embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope defined by the appended claims, so all changes and modifications falling within the scope of the claims or their equivalents should be covered by the appended claims.

Claims

1. A cylindrical secondary battery, characterized in that: include The battery cell is in the shape of a cylinder and has a positive electrode and a negative electrode; as well as, A battery controller is arranged at one end of the positive electrode or the negative electrode of the battery cell, and the battery controller includes: a circuit board and a positive electrode cap, Wherein, the circuit board comprises: a first surface and a second surface opposite to each other, and the second surface is welded with circuit components; The electrode cap is made of conductive metal and is soldered to the first surface of the circuit board in a patch manner. The first surface of the circuit board is provided with an electrode cap pad for soldering the electrode cap.

2. The cylindrical secondary battery according to claim 1, characterized in that: The electrode cap is a solid electrode cap, and both end surfaces of the solid electrode cap along the axial direction are solid planes.

3. The cylindrical secondary battery according to claim 1, characterized in that: The electrode cap pad has a channel, and the channel divides the electrode cap pad into at least two pad partitions.

4. The cylindrical secondary battery according to claim 1, characterized in that: The electrode cap is a hollow electrode cap with an inner cavity, and comprises a cylindrical cap body with one end open and a brim arranged around the open end of the cap body, and the open end of the electrode cap faces the circuit board.

5. The cylindrical secondary battery according to claim 4, characterized in that: The area where the cap body covers the circuit board is the cap body covering area, the area where the brim covers the circuit board is the brim covering area, the outer contour of each of the pad partitions is located within the outer contour of the brim covering area, and the inner contour of at least one of the pad partitions exceeds the brim covering area and extends inward into the cap body covering area.

6. The cylindrical secondary battery according to claim 4, characterized in that: The circuit board is provided with a glue injection hole and an exhaust overflow hole, the glue injection hole and the exhaust overflow hole are distributed in the cap body covering area, and the inner cavity of the electrode cap is filled with thermal conductive glue through the glue injection hole.

7. The cylindrical secondary battery according to claim 4, characterized in that: The battery controller also includes a controller shell with an inner cavity, the circuit board is accommodated in the inner cavity of the controller shell, the controller shell includes a controller outer shell made of metal, one end of the controller outer shell has a limit baffle, and the other end is an open end, a through hole is provided in the center of the limit baffle, the electrode cap extends out through the through hole of the limit baffle, a shell soldering pad is provided near the outer edge of the first surface of the circuit board, the circuit board is welded or crimped to the inner surface of the limit baffle through the shell soldering pad and is electrically connected to the inner surface of the limit baffle.

8. A cylindrical secondary battery, characterized in that: include The battery cell is in the shape of a cylinder and has a positive electrode and a negative electrode; as well as, A battery controller is arranged at one end where the positive electrode or negative electrode of the battery cell is located, and the battery controller comprises: a circuit board and a positive electrode cap, wherein the circuit board comprises: a first surface and a second surface opposite to each other, the electrode cap is made of a conductive metal material and is welded to the first surface of the circuit board, and circuit components are welded to the second surface; The inner electrode comprises an inner electrode fixing portion electrically connected to the circuit board and an inner electrode core welding platform bent relative to the inner electrode fixing portion, wherein the inner electrode core welding platform is used for welding the core, and an accommodation space for arranging circuit components is formed between the inner electrode core welding platform and the circuit board.

9. The cylindrical secondary battery according to claim 1, characterized in that: The inner electrode core welding platform and the inner electrode fixing portion are an integrally formed structure.

10. The cylindrical secondary battery according to claim 1, characterized in that: The circuit board is provided with an internal electrode pad for welding the internal electrode, and the internal electrode pad is the pad for accessing the positive electrode of the battery cell of the control circuit on the circuit board. After the internal electrode is welded and fixed to the internal electrode pad of the circuit board and an electrical connection is established, the internal electrode becomes a structural electrode for accessing the positive electrode of the battery cell to the circuit board control circuit.

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