Welding-free battery box for cylindrical batteries

Abstract

An all-welding-free battery box for cylindrical batteries comprises a support and cover plates, the support is divided into an upper support and a lower support, a plurality of cylindrical battery bins are arranged, the cover plates are divided into an upper cover plate and a lower cover plate, conductive contact pieces are arranged and connected with positive electrodes and negative electrodes of the batteries in the battery bins, and a protection plate bin is arranged on one side of the support. The conductive contact piece on at least one of the front face and the back face of the cover plate is detachably connected with the protection plate in the protection plate bin, the contact at least comprises a battery total negative electrode and a positive electrode of each string of batteries, the contact is composed of a male head and a female base, and at least one of the cover plate and the protection plate is selected to be provided with the female base for conducting and fixing. According to the invention, the structural design of double cover plates and the protection plate is adopted, the battery can be assembled without welding, different series-parallel connection schemes can be realized by changing the connection mode of the bracket, the protection plate and the cover plates, and the battery is simple in structure, convenient to disassemble, waterproof, and suitable for being used in the fields of electric vehicles, energy storage, base station standby power and the like.

Description

Technical Field

[0001] This invention relates to a device for installing batteries, and more particularly to a cylindrical battery box that requires no soldering. Background Technology

[0002] Lithium-ion batteries, as rechargeable batteries, are characterized by their small size, light weight, high energy density, long lifespan, environmental friendliness, and safety. They have gradually replaced lead-acid batteries in electric bicycles, electric motorcycles, electric tricycles, and new energy vehicles, especially cylindrical lithium-ion batteries. The performance indicators of individual cylindrical batteries, such as capacitance, impedance, and decay rate, are relatively consistent. They are typically assembled in series and parallel using spot welding technology. However, regardless of whether it's the initial resistance welding or later laser welding and ultrasonic welding, the inherent defects of the welding process cannot be avoided. Welding involves destructive assembly of individual batteries, with the possibility of incomplete welds or desoldering. Furthermore, welding requires specialized equipment, and disassembly after welding is difficult, hindering the widespread use and reuse of lithium-ion batteries. In recent years, weld-free battery boxes have emerged, offering significant advantages in terms of improved assembly efficiency, reduced equipment investment, lower technical requirements, and convenient disassembly and reuse. As a new technology, they are gradually gaining popularity and meeting people's DIY needs. However, currently known solderless battery boxes generally have shortcomings such as the lack of a design for a protection board installation location, the need for welding between the protection board and the battery, the inability to freely change series and parallel connection schemes, the lack of consideration for how to achieve waterproofing, and the non-standardization of the outer dimensions of the casing, which require further improvement.

[0003] To address the shortcomings of the aforementioned solderless battery boxes, recent patents have employed several methods to resolve these issues. Chinese patent CN209282291U, authorized for publication number CN209282291U, proposes a "solderless battery module," comprising a battery box, a battery pack, and a protection board. The battery box includes upper and lower covers. Conductive sheets are positioned at both ends of the battery pack, with series copper busbars connecting the conductive sheets. The protection board is located on the side of the battery box, with positive and negative terminals electrically connected to the total positive and negative terminals of the battery pack. The conductive sheets are spring-loaded busbars, including interconnected busbar springs. The positions of the busbar springs correspond one-to-one with the electrode positions at both ends of the individual battery cells. Each busbar spring includes a spring body and a pad. The spring body is located inside the upper and lower covers of the battery box, with an elastic protrusion at its center. A pad is positioned around the elastic protrusion, with the thickness of the pad being less than the height of the elastic protrusion. When the upper and lower covers of the battery box are locked with fasteners, the elastic protrusion makes close contact with the battery pack electrodes and undergoes elastic deformation, causing the battery pack electrodes to contact the pad. Although this technical solution includes a protective plate on the side of the battery box, the upper and lower covers are not flat, and the spring contacts are located inside the covers, making operation cumbersome, prone to errors, and unable to freely change series and parallel connection schemes. Chinese patent application CN111048709A proposes a "frame assembly for a cylindrical battery pack based on solderless technology," which consists of several sets of conductive elastic contact pieces with multiple protruding claw structures fixed between an insulating bracket and an insulating pressure plate. The end face of the insulating bracket has through holes, allowing the protruding claws of the conductive elastic contact pieces to contact the positive or negative terminals of the battery cells installed in the insulating bracket. The insulating pressure plate is fixed to the insulating bracket. The end face of the frame assembly for mounting the battery has a support structure, which fixes the upper and lower frame assemblies during battery pack assembly. This technical solution fixes the conductive elastic contact pieces between the insulating bracket and the insulating pressure plate, and the upper and lower frame assemblies are fixed by the support structure. However, the conductive elastic contact pieces need to be soldered to the protective plate, and the overall design does not consider how to achieve waterproofing.

[0004] Despite existing technologies employing various methods to address the problems of weld-free battery boxes, they still fall short of expectations. Given the high prices, inflated capacity claims, and questionable quality of finished battery packs on the market, coupled with the declining prices of lithium battery materials and individual cells, consumers, especially the owners of the 350 million electric bicycles nationwide, urgently need a battery box that truly eliminates the need for welding. This box should require only a screwdriver for assembly, have a simple structure, be easy to disassemble, and possess some waterproofing capabilities. Furthermore, rural women, unemployed youth, people with disabilities, and elderly people left behind in economically underdeveloped areas urgently need a marketable product with low market entry barriers, simple manufacturing processes, easy modular production, and user-friendly operation. With minimal training, individuals can easily start working and increase their income and enrich their lives. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of the prior art by providing a cylindrical battery box that eliminates the need for welding. This solution overcomes the problems of traditional weldless battery boxes, such as the lack of a designated mounting location for a protection plate, the requirement for welding between the protection plate and the battery, the inability to freely change series or parallel connection schemes, the lack of consideration for waterproofing, and the non-standardization of the casing's dimensions. This invention truly eliminates the need for welding, requiring only a screwdriver to assemble the battery. It meets the needs of consumers and manufacturers for weldless battery boxes when assembling battery packs, replacing traditional lead-acid batteries, reducing environmental pollution, protecting the environment, facilitating mass production in home-based industries, contributing to targeted poverty alleviation, and promoting rural revitalization.

[0006] The technical solution adopted by this invention to solve its technical problem is as follows: This invention provides a cylindrical battery box that requires no welding, including a support and a cover plate. The support is divided into an upper support and a lower support, and is provided with several battery compartments. The battery compartments are cylindrical. The cover plate is divided into an upper cover plate and a lower cover plate, and is provided with conductive contact pieces that are connected to the positive and negative terminals of the batteries in the battery compartments. A protection plate compartment is provided on one side of the support. At least one of the conductive contact pieces on the front and back of the cover plate is detachably connected to the protection plate in the protection plate compartment. The contact points include at least the total negative terminal of the battery and the positive terminal of each battery string. The contact points consist of a male connector and a female connector. At least one of the cover plate and the protection plate is provided with a female connector for conductive and fixing purposes.

[0007] As a further optimization of this solution, the bracket is a flat bracket, allowing the battery to freely enter and exit the battery compartment. Screw holes are set in the center of the four adjacent battery compartments, and screws are screwed through the cover plate and into the screw holes to secure the cover plate to the bracket.

[0008] As a further optimization of this solution, the cover plate is made of PCB and has several copper foils. The copper foils are independent of each other, and each copper foil is soldered with a conductive contact piece. A screw hole is set in the center of four adjacent copper foils. Screws are screwed through the screw holes into the bracket to fix the cover plate tightly to the bracket.

[0009] As a further optimization of this solution, the female seat adopts an L-shaped fixing seat, including a base surface and a bearing surface. The base surface is fixed to the protective plate, and the bearing surface is provided with screw holes. The base surface and the bearing surface are perpendicular to each other. Screws pass through the cover plate and are screwed into the screw holes to tightly fix the cover plate and the protective plate.

[0010] As a further optimization of this solution, the protection board includes an extension board, and a female connector is fixed on the extension board. The extension board is long and narrow, and the protection board and the extension board are detachably connected. Each extension board in each battery compartment is provided with a female connector.

[0011] As a further optimization of this solution, the side plates around the bracket are at least 1.5 mm higher than the outer surface of the bracket. After the cover plate is fixed to the bracket, the outer surface of the cover plate is not higher than the edge of the side plate of the bracket.

[0012] As a further optimization of this solution, the support structure is a split type, including an upper support, a lower support, and tubular columns. The upper and lower supports have slots on their four side plates. There are at least three tubular columns, one end of which is connected to the upper support and the other end of which is connected to the lower support.

[0013] As a further optimization of this solution, the upper and lower supports are spliced ​​together, consisting of a central support and surrounding supports, with slots on the edges of the supports that allow them to be interlocked and connected as a whole.

[0014] As a further optimization of this solution, the bracket adopts an integrated design, consisting of an upper bracket, a lower bracket, and four side plates, which are injection molded in one piece.

[0015] As a further optimization of this solution, the bracket is equipped with a terminal compartment. The terminal compartment is cylindrical with an open top surface and a hole on the bottom surface. There are two terminal compartments, and terminals are installed inside. The bottom diameter of the terminal compartment is larger than the diameter of the terminal. After the terminal is installed into the terminal compartment, the gap is filled with waterproof material.

[0016] The beneficial effects of this invention are as follows: This invention adopts a "double cover plate + protection plate" structural design, which truly achieves complete welding-free assembly. Only a screwdriver is needed to assemble the battery. By changing the connection method of the bracket, protection plate, and cover plate, different series and parallel connection schemes can be achieved. The bracket's external dimensions are standardized, allowing direct replacement of the original lead-acid battery. This transforms series connection into parallel connection, increasing battery life and improving current output capability. The battery box is waterproof, has a simple structure, and is easy to disassemble. It effectively solves the long-standing problems of spot welding and disassembly in the lithium battery industry, contributing to the promotion and reuse of lithium-ion batteries. It is highly suitable for use in electric bicycles, electric motorcycles, electric tricycles, solar and wind energy storage, as well as backup power supplies for communication base stations and automotive starting power supplies. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the first embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the 16S10P splicing bracket structure.

[0019] Figure 3 This is a schematic diagram of the protective plate structure.

[0020] Figure 4 This is a schematic diagram of the conductive contact sheet structure.

[0021] Figure 5 This is a schematic diagram of the structure of the second embodiment of the present invention.

[0022] Figure 6 This is a schematic diagram of the front structure of the 13S6P cover plate.

[0023] Figure 7 This is a schematic diagram of the back structure of the 16S5P cover plate.

[0024] Figure 8 This is a schematic diagram of a bracket structure with a terminal compartment.

[0025] Figure 9 This is a schematic diagram of the fuse compartment structure.

[0026] Figure 10 This is a schematic diagram of the SMT tape and reel spring structure.

[0027] In the diagram, 1. Upper bracket, 2. Lower bracket, 3. Battery compartment, 4. Upper cover plate, 5. Lower cover plate, 6. Conductive contact piece, 7. Battery, 8. Protection board compartment, 9. Protection board, 10. Screw hole, 11. Post, 12. Slot, 13. Insulating plate, 14. Expansion plate, 15. L-shaped mounting base, 16. Recessed rail, 17. Copper foil, 18. Metal connecting piece; 19. Copper strip; 20. Terminal compartment; 21. Fuse compartment; 22. Fuse tube socket. Implementation

[0028] Reference Figure 1 and Figure 5 As shown, this invention provides a cylindrical battery box that requires no welding, comprising a support and a cover. The support is divided into an upper support 1 and a lower support 2, each with a plurality of battery compartments 3. The battery compartments 3 are cylindrical, and the center lines of the battery compartments 3 at corresponding positions on the upper support 1 and the lower support 2 overlap. The cover is divided into an upper cover 4 and a lower cover 5, with the side in contact with the support being the front and the other side being the back. The front of the upper cover 4 and the lower cover 5 are respectively provided with a plurality of conductive contact pieces 6, which are connected to the positive or negative terminals of the batteries 7 inside the battery compartments 3. A protective plate compartment 8 is provided on one side of the support. At least one of the conductive contact pieces 6 on the front and back of the cover is detachably connected to the protective plate 9 inside the protective plate compartment 8. The contact point includes at least the total negative terminal of the battery and the positive terminal of each battery string. The negative terminal of the first battery string 7 is the total negative terminal of the battery, and the positive terminal of the last battery string 7 is the total positive terminal of the battery. The contact point consists of a male connector and a female connector. At least one of the cover and the protective plate 9 is provided with a female connector, which serves both conductive and fixing functions.

[0029] Specifically, in Figure 1In the first embodiment shown, the bracket adopts a split design, including an upper bracket 1, a lower bracket 2, and tubular columns 11. The upper bracket 1 and lower bracket 2 are planar brackets, meaning the surface of the bracket that contacts the cover plate is flat. Each bracket is 3–10 mm thick. The bottom diameter of the battery compartment 3 is 10–46.3 mm. No limiting plates are provided on the upper and lower bottom surfaces, allowing the battery 7 to freely enter and exit. Screw holes 10 are provided at the center of four adjacent battery compartments 3. The screw holes 10 are cylindrical, with a bottom diameter of 3–5 mm, serving to fix the cover plate. Screws pass through the cover plate and are screwed into the screw holes 10 to tightly fix the cover plate to the bracket. Tubular columns 11 are provided between the upper bracket 1 and lower bracket 2, with at least three columns 11, serving to fix the bracket. Slots 12 are provided on the four side plates of the upper bracket 1 and lower bracket 2. Each slot 12 includes an opening and a bottom. The openings of the slots 12 on the four side plates of the upper bracket 1 all face downwards, while the openings of the slots 12 on the four side plates of the lower bracket 2 all face upwards. The spacing between the inner walls of the slots 12 is 1–2.5 mm. An insulating plate 13, 1–2.5 mm thick, is inserted between the two slots 12. There are four insulating plates 13, each with the same width. The bottom of the slot 12 is at least 1.5 mm higher than the outer surface of the bracket. After fixing the cover plate to the bracket, the outer surface of the cover plate is not higher than the outer edge of the slot bottom. Alternatively, the insulating plate 13 may not be added between the slots 12, for example, when several brackets are connected in parallel, with a larger battery box externally. The upper bracket 1 and lower bracket 2 are spliced, composed of a central bracket and surrounding brackets (see...). Figure 2 The bracket includes single-unit, double-unit, and multi-unit configurations. Each bracket has at least two sides with slots, and each side has two slots. The slots include protrusions and recesses, which are interlocked to form a single unit. This embodiment uses a modular bracket design. The advantage of this design is that the series and parallel connection schemes can be freely changed as needed, allowing for flexible assembly of various battery pack models.

[0030] The protection board compartment 8 is located on the same side of the upper bracket 1 and the lower bracket 2, and consists of an upper compartment and a lower compartment. The upper compartment is located on the upper bracket 1, and the lower compartment is located on the lower bracket 2. The protection board 9 is flat, with the side for soldering electronic components being the front and the other side being the back. It is located between the upper and lower compartments. The protection board 9 includes an extension board 14, which is made of PCB and is long and narrow. Each extension board 14 in each row of battery compartments 3 has a female connector. Except for the total negative and total positive terminals of the battery, adjacent female connectors can be shorted as needed. The side for soldering the female connector is the front, and the other side is the back. There are two extension boards 14, and their backs are fixed to the two sides of the front of the protection board 9, respectively. The fixing method includes adhesive (see...). Figure 3The female connector, specifically the L-shaped mounting bracket 15, consists of a base surface and a bearing surface, which are perpendicular to each other. The base surface is welded to the extension plate 14, and the bearing surface has screw holes 10. Screws pass through the cover plate and are screwed into the screw holes 10 to tightly fix the cover plate to the extension plate 14. The L-shaped mounting bracket 15 is preferably made of copper and tin-plated to prevent oxidation and facilitate welding. In this embodiment, the protection board 9 uses the extension plate 14. The advantage of this design is that the extension plate 14 of a suitable length can be cut according to the series and parallel connection of the battery pack without changing the external dimensions of the protection board 9. The protection board 9 is available in two models: lithium iron phosphate and ternary lithium, supporting protection of 1 to 17 battery cells. By changing the connection method of the protection board 9, multiple uses can be achieved with a single board.

[0031] The upper cover 4 and lower cover 5 are flat and consist of an insulating plate 13 and conductive contact pieces 6. The insulating plate 13 is made of FR-4 fiberglass board or 3240 epoxy board. The side that fixes the conductive contact piece 6 is the front, and the other side is the back. According to the distribution of the battery compartment 3, corresponding patterns are printed on the front of the insulating plate 13 to indicate the fixing position of the conductive contact piece 6 and the location of the screw holes 10. The conductive contact piece 6 is elongated, and an elastomer is provided at the part that contacts the positive and negative terminals of the battery 7. The elastomer is ⊕-shaped, 5-8 mm in diameter, with a cross-shaped opening, and flares outwards, possessing inherent elasticity (see...). Figure 4 The conductive contact piece 6 is preferably made of copper, especially phosphor bronze, which has strong fatigue resistance, high hardness, and good elasticity, ensuring good contact. The surface is nickel-plated or tin-plated to prevent oxidation. Fixing methods include adhesive bonding, embedding, and riveting. The screw holes 10 include two types: connecting brackets and connecting protective plates 9. Screws pass through the screw holes 10 and are screwed into the brackets to tightly fix the cover plate to the brackets. Screws also pass through the screw holes 10 and are screwed into the L-shaped fixing seat 15 to tightly fix the cover plate to the protective plate 9. Screws are especially flat-head screws, and screw holes 10 are especially countersunk screw holes. In this embodiment, the conductive contact piece 6 uses copper, which has better conductivity than nickel-plated steel strips produced by spot welding.

[0032] exist Figure 5In the second embodiment shown, the bracket adopts an integrated design, consisting of an upper bracket 1, a lower bracket 2, and four side plates, all injection molded in one piece. The upper bracket 1 and lower bracket 2 are planar brackets, set inside the four side plates. The upper bracket 1 and lower bracket 2 have several battery compartments 3, from which batteries 7 can freely enter and exit. A screw hole 10, cylindrical in shape, is provided at the center of four adjacent battery compartments 3. The upper cover plate 4 is detachably connected to the upper bracket 1, and the lower cover plate 5 is detachably connected to the lower bracket 2. The surface of the bracket in contact with the cover plate is the front, and the other side is the back. The four side plates include an upper side plate, a lower side plate, a left side plate, and a right side plate, all four side plates forming a single unit. The cover plate extends at least 1.5 mm above the front of the upper bracket 1 and lower bracket 2. After the cover plate is fixed to the bracket, its outer surface does not exceed the edge of the four side plates. To increase stability, at least four tubular columns 11 are installed between the upper support 1 and the lower support 2 during the design and fabrication of the injection mold. These columns are positioned at the upper left, upper right, lower left, and lower right of the support, respectively, to prevent deformation of the support. Alternatively, the tubular columns 11 can be omitted before injection molding and added afterward. The tubular columns 11 are cut to a suitable length, and the screw holes 10 of the upper support 1 and lower support 2 are designed as countersunk screw holes. Flat-head screws pass through the screw holes 10 and are tightly fixed to the tubular columns 11. In this embodiment, it is preferable to add the tubular columns 11 to the injection mold. The advantage of this design is that it avoids the screws at both ends of the later-added tubular columns 11 occupying the screw holes 10, preventing the upper cover plate 4 and lower cover plate 5 from screwing screws into the screw holes 10.

[0033] As a preferred design, the bracket measures 179–183 mm in length, 68–79 mm in width, and 168–172 mm in height. The bottom diameter of the battery compartment 3 is 18.4 mm, capable of accommodating 18650 batteries. The battery compartments 3 of the upper bracket 1 and lower bracket 2 are arranged in 9 rows × 9 columns, side by side, with a center-to-center distance of 19 mm. The external dimensions of the bracket are consistent with the specifications of the 6-DZF-20 lead-acid battery specified in the national standard "Valve-regulated Lead-acid Batteries for Electric Bicycles Part 2: Product Varieties and Specifications" (GB / T 22199.2-2017). This battery model is another common lead-acid battery model on the market besides the 6-DZF-12 model, with a nominal voltage of 12 V, a rated capacity of 20 Ah, and external dimensions of 181±2 mm in length, 77±2 mm in width, 170±2 mm in height, and a total height of 175 mm. The bracket's dimensions are designed according to national standards for lead-acid batteries. It can replace the original 6-DZF-20 lead-acid batteries without altering the shape and size of the electric vehicle's battery compartment, changing the connection from series to parallel, increasing battery range and improving current output. Under current technology, each 6-DZF-20 lead-acid battery weighs 7 kg, and four batteries connected in series weigh 28 kg, providing a range of 60 km. However, if this invention is implemented, using 18650 power batteries with a single 2950mAh capacity, each battery pack can hold 78-80 individual cells, weighing 4 kg each. Four battery packs connected in parallel weigh 16 kg, providing a range of 240 km. This significantly surpasses the performance of lead-acid batteries and effectively meets the higher requirements for battery capacity and performance in logistics delivery, long-distance travel, and high-power electric vehicles. It also brings good news to owners of the 350 million electric bicycles nationwide who suffer from "range anxiety."

[0034] The protection plate compartment 8 is located on the left or right side of the bracket, which maximizes space utilization. A recessed rail 16 is installed on the inner side panel of the compartment. One set of opposite sides of the protection plate 9 is welded with L-shaped fixing seats 15, while the edge of the other set of opposite sides has a gap of at least 1.5 mm. It is inserted vertically along the recessed rail 16 from the upper bracket 1 to the lower bracket 2. When the recessed rail 16 is positioned close to the side panel, the front of the protection plate 9 faces the battery compartment 3; when the recessed rail 16 is positioned close to the battery compartment 3, the front of the protection plate 9 faces the side panel. When the positive electrode material of the battery 7 installed in the battery compartment 3 is lithium manganese oxide, lithium cobalt oxide, or ternary lithium, the protection plate 9 adopts a 13S6P design; when the positive electrode material of the battery 7 installed in the battery compartment 3 is lithium iron phosphate, the protection plate 9 adopts a 16S5P design. When the protection board 9 adopts the 13S6P design, it has at least 14 L-shaped mounting brackets 15 for connecting the positive and negative terminals of the battery 7, marked B-, B1~B12, and B+. When the protection board 9 adopts the 16S5P design, it has at least 17 L-shaped mounting brackets 15 for connecting the positive and negative terminals of the battery 7, marked B-, B1~B15, and B+. The protection board 9 also needs to have 2 L-shaped mounting brackets 15 for charging and discharging, marked PC+ and PC-. PC+ is connected to the battery's total positive terminal B+, and PC- is connected to the battery's total negative terminal B-. PC- serves as both the charging and discharging negative terminal, employing a single charging / discharging port design, simplifying the circuit and ensuring protection during both charging and discharging. In this embodiment, the rated voltage of the protection board 9 is 48V, which meets the technical requirements for the nominal voltage of batteries in the mandatory national standard "Safety Technical Specifications for Electric Bicycles" (GB 17761-2018).

[0035] The upper cover 4 and lower cover 5 are made of PCB, which is made of single-sided or double-sided copper-clad laminate. The copper-clad laminate is preferably FR-4 copper-clad laminate, which has excellent flame retardancy, a board thickness of 1.5-2 mm, and a copper foil thickness of 35-70 μm, preferably 70 μm, with a large current carrying capacity. The side of the copper-clad laminate that contacts the bracket is the front side, and the other side is the back side. Several copper foils 17 are set on the front side of the copper-clad laminate. They are all the same size, independent of each other, and circular. The diameter of the copper foil 17 is not greater than the bottom diameter of the battery compartment 3. The surface is tin-plated to prevent oxidation, increase current carrying capacity, and facilitate soldering. Each copper foil 17 is soldered with a conductive contact piece 6. Screw holes 10 are set in the center of four adjacent copper foils 17 as needed. The diameter of the screw holes 10 is 3-5 mm. Screws are screwed through the screw holes 10 and screwed into the bracket to tightly fix the cover plate to the bracket. The screws are especially flat-head screws, and the screw holes 10 are especially countersunk screw holes. The conductive contact piece 6, especially the spring-loaded piece, has a regular shape and a tin-plated surface, making it easier to solder onto the PCB. In this embodiment, an SMT tape-reel phosphor bronze spring-loaded piece is preferred. The spring-loaded piece is tape-reeled for easy automatic soldering by the bonding machine (see...). Figure 6 , Figure 10Solder is applied between the copper foils to conduct electricity. To increase current carrying capacity, a metal connecting piece 18 is soldered between adjacent copper foils 17. The metal connecting piece 18 is rectangular, 8-12 mm wide, and preferably made of copper sheet with a tin-plated surface. Compared to brass and phosphor bronze, copper has a higher copper content and can be considered approximately pure copper, resulting in superior conductivity. When the protection board 9 adopts the 13S6P scheme, a single-sided copper-clad board is preferred for the PCB, although a double-sided copper-clad board is also possible. The circuitry on the front and back sides is consistent, and each copper foil 17 has a via. The copper foil on the back side increases the current carrying capacity. When the protection board 9 adopts the 16S5P scheme, a double-sided copper-clad board is preferred for the PCB. Copper foil is placed on the back side, and it is strip-shaped. One end is connected to the copper foil 17 on the front side through a via, and the other end is connected to the L-shaped mounting base 15 of the protection board 9 through a screw. Copper strips 19 can also be soldered onto the back copper foil to increase the current carrying capacity (see...). Figure 7 Since the number of copper foil strips required on the back is small, a single-sided copper-clad board can be used for the PCB, with copper strips 19 directly fixed to the back. Fixing methods include adhesive bonding, embedding, and riveting. The outer surfaces of the upper cover 4 and lower cover 5 are waterproofed, including applying waterproof material, installing insulating boards, and applying fiberglass tape, to reduce the possibility of external water entering the casing and to meet the IP68 technical requirements of the International Electrotechnical Commission (IEC) standard 60529-2013 "Degrees of Protection Provided by Enclosures (IP Code)". This ensures that even when the entire battery pack is submerged in water under certain pressure for an extended period, external water cannot enter the casing. In this embodiment, the cover uses independent copper foil 17 and conductive contact pieces 6, with solder applied or metal connecting pieces 18 welded. The advantage of this design is that it allows for flexible changes in series and parallel connection schemes.

[0036] The bracket has a terminal compartment 20 on the upper side plate (see...) Figure 8 The terminal compartment 20 is cylindrical with a bottom diameter of 12–14 mm. The top surface is open, and the bottom surface has a circular hole. There are two terminal compartments 20: one for installing the positive terminal and the other for installing the negative terminal. Both the positive and negative terminals use M5 knurled copper nuts with an inner diameter of 5 mm and an outer diameter of 8.3–10.3 mm. These are blind holes, meaning the upper and lower screw holes of the terminal are not connected, preventing external water from seeping into the bracket through the nut. The wires have copper lugs at both ends; one end is fixed to the lower screw hole of the terminal, and the other end connects to the battery's main positive or main negative terminal on the protection board 9. The wire connecting the positive terminal and the main positive terminal is red, while the wire connecting the negative terminal and the main negative terminal is black or blue. After inserting the positive and negative terminals into the terminal compartment 20, fill the gaps in the terminal compartment 20 with sealant. The positive terminal is filled with red sealant, and the negative terminal with black or blue sealant, serving both waterproofing and polarity indication purposes. In this embodiment, the terminal compartment 20 is provided on the side plate of the bracket for convenient electrical appliance connection.

[0037] A fuse compartment 21 is provided between the two terminal compartments 20 (see Figure 9 The fuse compartment 21 is a rectangular cavity, 20–24 mm long, 8–12 mm wide, and 10–14 mm deep. A fuse holder 22 is installed inside, secured by direct pre-embedded injection molding or post-sealing, providing excellent waterproofing and preventing external water from entering the bracket. There are two fuse holders 22: one connects to the positive terminal of the battery on the protection board 9, and the other connects to the positive terminal of the terminal compartment 20. The fuse tube has a glass or ceramic shell, 5 mm in diameter and 20 mm in length, providing overcurrent and overheat protection. The fuse compartment 21 has a removable, insulated cover with a wing on each of its two longer sides. Each wing has a screw hole 10, 2–4 mm in diameter. A stud is installed on the bracket; screws pass through the screw holes 10 and are screwed into the studs to secure the cover to the bracket. The screws are flat-head screws, and the screw holes 10 are countersunk holes. The outer surface of the cover is flush with the upper side plate of the bracket. A sealing ring is placed between the cover and the fuse compartment 21 for waterproofing. As an optional feature, the fuse compartment 21 is provided with two flat sockets for installing blade-type automotive fuses. In this embodiment, the fuse compartment 21 is designed on the upper side plate of the bracket, which enhances the system's safety.

[0038] Compared to the modular bracket in the first embodiment, this embodiment uses an integrated bracket, which is more stable, has a better sealing effect, is easier to waterproof, and makes PACK assembly more efficient and time-saving. Furthermore, its dimensions can be designed according to national standards for lead-acid batteries. Standardizing the battery box's dimensions allows for direct replacement of existing lead-acid batteries without altering the shape and size of the electric vehicle's battery compartment. This transforms series-connected batteries into parallel-connected ones, maximizing the electric vehicle's range and improving the battery pack's current output capacity. This meets the higher requirements for battery capacity and performance in logistics delivery, long-distance travel, and high-power electric vehicles, and brings good news to owners of the 350 million electric bicycles nationwide who suffer from "range anxiety."

[0039] A method for assembling cylindrical batteries without welding includes the following steps: (i) determining the series-parallel combination scheme of the protection board based on the nominal voltage and positive electrode material of the battery pack; (ii) fabricating the upper and lower cover plates according to the external dimensions of the battery box and fixing the conductive contact pieces; (iii) installing the terminals into the terminal compartment, filling with sealant, and connecting the terminals and the protection board at both ends of the wires respectively; (iv) inserting the protection board into the protection board compartment, fixing the lower cover plate and the bracket, and fixing the lower cover plate and the protection board; (v) installing the batteries one by one into the battery compartment, fixing the upper cover plate and the bracket, and fixing the upper cover plate and the protection board; (vi) insulating the back of the upper and lower cover plates and taking waterproof measures for the outside of the battery box.

[0040] In summary, this invention employs a "double cover plate + protection plate" structural design, achieving truly complete solderlessness. Battery assembly requires only a screwdriver. By changing the connection methods of the bracket, protection plate, and cover plate, different series and parallel connection schemes can be achieved. The battery box is waterproof, structurally simple, and easy to disassemble, effectively solving the long-standing spot welding and disassembly problems plaguing the lithium battery industry. This contributes to the promotion and reuse of lithium-ion batteries and is highly practical. This invention has not been previously patented or publicly disclosed in domestic or international publications, nor has it been publicly used domestically or otherwise made known to the public. This "conductive connection of the cover plate..." The battery box, where the contact plates and the protective plate inside the bracket compartment are connected via a male and female connector, is a new product. This product is unprecedented in nature, representing the result of human application of natural laws to specific objects, thus possessing novelty. Compared to existing technologies, this invention has outstanding substantive features and significant progress, overcoming the shortcomings and deficiencies of existing technologies. One independent claim and nine dependent claims are not obvious to a person skilled in the art. Compared to the closest prior art, it produces beneficial technical effects such as "truly achieving complete solderlessness, freely interchangeable series and parallel connection schemes, and easier implementation of waterproofing," demonstrating inventiveness. This invention can be industrially mass-produced, achieving good economic and social benefits. It can positively impact the development of family handicrafts, aiding targeted poverty alleviation and promoting rural revitalization, and replacing lead-acid batteries to reduce environmental pollution and protect the environment. It is highly suitable for use in electric vehicles, energy storage, and base station backup power applications.

[0041] The above description is merely a preferred embodiment of the present invention, used to explain the invention rather than to limit it. Those skilled in the art can make improvements or modifications based on the above description. For example, in the second embodiment, the upper and lower cover plates employ different series-parallel combination schemes, including 1S80P, 2S40P, 3S26P, 4S20P, 5S16P, 6S13P, 7S11P, 8S10P, 9S9P, 10S8P, 11S7P, 12S6P, 14S5P, 15S5P, 17S4P, 18S4P, 19S4P, 20S4P, 21S3P, 22S3P, 23S3P, 24SP, 25S3P, 26S3P, 27S3P, etc.; the female connector can be a six-sided nut, a screw wire frame, or a U-shaped terminal block; the cover plate and the protective plate are connected by a plug. The socket is connected in the following way: the female connector is located on the cover plate; the copper foil on the front of the cover plate PCB is rectangular; the terminal compartment is located in a cylindrical container, which houses a battery compartment of the bracket; the bracket adopts the external dimensions of lead-acid batteries of specifications such as 6-DZF-12, 6-EVF-32, 6-EVF-45, 6-EVF-58, or others; the cylindrical batteries adopt models such as 10400, 14500, 16340, 21700, 26650, 32650, and 46160; the battery compartment adopts a staggered design; the cylindrical batteries are sodium-ion batteries; after the promulgation of the mandatory national standard "Safety Requirements for Lithium-ion Batteries for Electric Bicycles", corresponding changes were made according to the standard, and all these improvements and modifications should be included within the scope of protection of this invention within the framework of the independent claims of this invention.

Claims

1. A cylindrical battery box that requires no welding, comprising a support frame and a cover plate, the support frame being divided into an upper support frame and a lower support frame, and having a plurality of battery compartments, the battery compartments being cylindrical, and the cover plate being divided into an upper cover plate and a lower cover plate, and having conductive contact pieces provided for connecting to the positive and negative terminals of the batteries inside the battery compartments, characterized in that: A protective plate compartment is provided on one side of the bracket. At least one conductive contact piece on the front and back of the cover plate is detachably connected to the protective plate inside the protective plate compartment. The contact includes at least the total negative terminal of the battery and the positive terminal of each battery string. The contact consists of a male connector and a female connector. At least one of the cover plate and the protective plate is provided with a female connector for conductive and fixing purposes.

2. The cylindrical battery box with no welding required according to claim 1, characterized in that: The bracket is a flat bracket, allowing the battery to move freely into and out of the battery compartment. Screw holes are set in the center of the four adjacent battery compartments, and screws are screwed through the cover plate and into the screw holes to secure the cover plate to the bracket.

3. The cylindrical battery box with no welding required according to claim 1, characterized in that: The cover plate is made of PCB and has several copper foils. The copper foils are independent of each other. Each copper foil is soldered with a conductive contact piece. A screw hole is set in the center of four adjacent copper foils. Screws are screwed through the screw holes into the bracket to fix the cover plate tightly to the bracket.

4. The cylindrical battery box that requires no welding according to claim 1, characterized in that: The female seat adopts an L-shaped fixing seat, including a base surface and a bearing surface. The base surface is fixed to the protective plate, and the bearing surface is provided with screw holes. The base surface and the bearing surface are perpendicular to each other. Screws pass through the cover plate and are screwed into the screw holes to tightly fix the cover plate and the protective plate.

5. The cylindrical battery box with no welding required according to claim 1, characterized in that: The protection board includes an extension board, and a female connector is fixed on the extension board. The extension board is long and narrow. The protection board and the extension board are detachably connected. Each extension board in each battery compartment is equipped with a female connector.

6. The cylindrical battery box with no welding required according to claim 1, characterized in that: The side plates of the bracket should be at least 1.5 mm higher than the outer surface of the bracket. After the cover plate is fixed to the bracket, the outer surface of the cover plate should not be higher than the edge of the side plate of the bracket.

7. The cylindrical battery box with no welding required according to claim 1, characterized in that: The support system is modular, consisting of an upper support, a lower support, and tubular columns. The upper and lower supports have slots on their four side plates. There are at least three tubular columns, one end of which is connected to the upper support and the other end to the lower support.

8. The cylindrical battery box with no welding required according to claim 7, characterized in that: The upper and lower supports are spliced ​​together, consisting of a central support and surrounding supports. The edges of the supports are provided with slots, which are then interlocked to form a whole.

9. The cylindrical battery box that requires no welding according to claim 1, characterized in that: The bracket is a one-piece design, consisting of an upper bracket, a lower bracket, and four side plates, all injection molded in one piece.

10. The cylindrical battery box with no welding required according to claim 9, characterized in that: The bracket is equipped with a terminal compartment, which is cylindrical with an open top and a hole on the bottom. There are two terminal compartments, and terminals are installed inside. The bottom diameter of the terminal compartment is larger than the diameter of the terminal. After the terminal is installed in the terminal compartment, the gap is filled with waterproof material.

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