A lead-acid storage battery

Abstract

This invention relates to a lead-acid battery, belonging to the field of lead-acid battery technology, to solve the problems of uneven current distribution and short cycle life of existing lead-acid batteries. The lead-acid battery includes a single cell, which comprises multiple positive and negative plates arranged in alternating layers. Each positive and negative plate includes a frame and tabs. The frame includes an upper frame, a lower frame, a left frame, and a right frame. Each positive and negative plate has a first tab and a second tab, symmetrically arranged along the length of the upper frame. The plane containing the first and second tabs is parallel to the plate surface. In the positive plate, the distance between the first and second tabs is d1; in the negative plate, the distance between the first and second tabs is d2, where d1 and d2 are different. In the positive plate, the first and second tabs are of the same size. The lead-acid battery of this invention has a long service life.

Description

Technical Field

[0001] This invention relates to the field of lead-acid batteries, and more particularly to a lead-acid battery. Background Technology

[0002] Lead-acid batteries have been around for over a century and are one of the most widely used chemical power sources globally. Their raw materials are abundant, inexpensive, and recyclable. A battery mainly consists of positive and negative plates, separators, a battery casing, and other components. The plates primarily consist of grids and active materials. Traditional lead-acid battery grids are composed of thick side frames and tabs, mainly used to support the positive and negative electrochemical active materials and to collect the current flowing through the tabs.

[0003] Therefore, in addition to ease of forging, the grid design should also meet the requirements of good contact and mechanical properties between the grid surface and the active material, while ensuring uniform current distribution throughout the entire plate and minimizing ohmic voltage drop. Currently, battery grids on the market are generally single-tab grids, with the positive and negative tabs on one side of the grid. This design leads to uneven utilization of the active material on the upper and lower parts of the plate, resulting in a concentration difference in the electrolyte and severely affecting the battery's lifespan. During high-current charging and discharging, the internal resistance increases sharply, potentially causing thermal runaway and damaging the battery. CN103840173B discloses a bitab grid, which includes an upper frame, a lower frame and a left frame corresponding to the upper frame, a right frame opposite to the left frame, and several vertical and horizontal ribs arranged in a crisscross pattern. The grid also includes two tabs located on the upper and lower frames of the grid, respectively, and arranged diagonally. This bitab grid suffers from complex manufacturing processes and requires high sealing.

[0004] Existing lead-acid battery grid structures result in uneven current distribution within the plates, large ohmic voltage drop, short cycle life, or complex manufacturing processes. Summary of the Invention

[0005] In view of the above analysis, the present invention aims to provide a lead-acid battery that can solve at least one of the following problems: (1) the current distribution inside the plates of existing lead-acid batteries is uneven, the ohmic voltage drop is large, and the cycle life of the battery is short; (2) the existing lead-acid battery manufacturing process is complicated.

[0006] This invention provides a lead-acid battery, the lead-acid battery comprising a single cell, the single cell comprising a plurality of positive plates and a plurality of negative plates alternately stacked; each of the positive plates and each of the negative plates comprises a frame and a tab, the frame comprising an upper frame, a lower frame, a left frame and a right frame;

[0007] Each positive electrode plate and each negative electrode plate has a first electrode plate and a second electrode plate. The first electrode plate and the second electrode plate are symmetrically arranged on the upper frame along the length direction of the upper frame. The plane containing the first electrode plate and the second electrode plate is parallel to the electrode plate surface. In the positive electrode plate, the distance between the first electrode plate and the second electrode plate is d1. In the negative electrode plate, the distance between the first electrode plate and the second electrode plate is d2. d1 and d2 are different. In the positive electrode plate, the first electrode plate and the second electrode plate have the same size.

[0008] Furthermore, in the negative electrode plate, the first tab and the second tab are of the same size.

[0009] Furthermore, the length of the upper border is L1, where L1 ≥ d1 > d2.

[0010] Furthermore, the length of the upper border is L1, where L1≥d2>d1.

[0011] Furthermore, in the positive electrode plate of the single cell, the top of the first tab is a first positive busbar, which connects multiple positive electrode plates with their first tabs in parallel; the top of the second tab is a second positive busbar, which connects multiple positive electrode plates with their second tabs in parallel.

[0012] In the negative electrode plate of the single cell, the top of the first tab is the first negative busbar, which connects the first tabs of multiple negative electrode plates in parallel; the top of the second tab is the second negative busbar, which connects the second tabs of multiple negative electrode plates in parallel.

[0013] Furthermore, multiple ribs are also provided within the frame.

[0014] Furthermore, the ribs include multiple first ribs distributed laterally along the electrode plate surface and multiple second ribs distributed longitudinally along the electrode plate surface, wherein the first ribs and the second ribs intersect perpendicularly.

[0015] Furthermore, the ribs include multiple first ribs distributed laterally along the electrode surface and multiple second ribs distributed longitudinally along the electrode surface; the second ribs located on the vertical line of the upper frame are rectangular, and the shape of the remaining second ribs is such that the width of the second ribs gradually decreases along the direction away from the upper frame.

[0016] Furthermore, the first ribs are all V-shaped with their openings facing the upper frame.

[0017] Furthermore, the first rib is distributed with sparser ribs at the top and denser ribs at the bottom.

[0018] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0019] (1) The lead-acid battery provided by this invention optimizes the tab structure, with both tabs of the positive and negative plates symmetrically located on the left and right sides of the upper frame, resulting in uniform current distribution across the entire plate surface and reduced potential loss. This reduces heat generation during high-current charging and discharging, which is beneficial for high-power operation and extends battery life.

[0020] (2) The positive and negative plates of the lead-acid battery of the present invention are both bipolar tabs. The bipolar tabs of the negative plate further improve the power characteristics and promote a more uniform current distribution during charging and discharging. Furthermore, the different positions of the tabs of the positive and negative plates are conducive to welding the busbars. The manufacturing process is simple and suitable for large-scale production.

[0021] (3) The positive plate of the lead-acid battery of the present invention adopts a bipolar plate grid structure, and the second rib on the vertical line of the upper frame of the bipolar plate grid is rectangular, which plays the role of reinforcing rib and can improve the creep resistance of the middle part of the plate; the remaining second ribs are thicker at the top and thinner at the bottom, which can be beneficial to the corrosion resistance and current collection of the upper part.

[0022] (4) The positive plate of the lead-acid battery of the present invention adopts a bipolar plate grid structure, and the first rib is V-shaped, which can improve the creep resistance of the grid; the distribution of the first rib is sparse at the top and dense at the bottom, which is conducive to improving the utilization rate of the active material at the bottom of the plate; the upper part of the first rib is thicker and the lower part of the first rib is thinner, which can reduce the cost while reducing the corrosion of the rib.

[0023] (5) The thickness of the negative plate of the lead-acid battery of the present invention is less than that of the positive plate, and the number of ribs of the negative plate is less than that of the positive plate. This can reduce production costs while ensuring battery performance, resulting in significant economic benefits.

[0024] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description

[0025] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0026] Figure 1 This is a schematic diagram of the structure of the single-pole lug grid in Example 1;

[0027] Figure 2 This is a schematic diagram of the bipolar lug grid structure in Example 2;

[0028] Figure 3a This is a schematic diagram of the bipolar lug grid structure in Example 3;

[0029] Figure 3b This is a schematic diagram of another structure of the bipolar lug grid in Example 3;

[0030] Figure 4a This is a schematic diagram of the battery structure in Example 4;

[0031] Figure 4b This is a schematic diagram of the battery structure in Example 4;

[0032] Figure 5 This is a schematic diagram of the battery structure in Example 4;

[0033] Figure 6 This is a schematic diagram of the battery structure in Example 4;

[0034] Figure 7a This is a schematic diagram of the structure of the battery in Example 5;

[0035] Figure 7b This is a schematic diagram of the structure of the battery in Example 5;

[0036] Figure 8 This is a schematic diagram of the structure of the battery in Example 5;

[0037] Figure 9a This is a schematic diagram of the structure of the battery in Example 5;

[0038] Figure 9b This is a schematic diagram of the structure of the battery in Example 5;

[0039] Figure 10 Internal view of a 1×6 structure battery fabricated using a traditional single-tab electrode plate;

[0040] Figure 11 This is a schematic diagram illustrating the cycle performance of the battery.

[0041] Figure 12a This is a comparison of the temperature distribution of batteries prepared according to embodiments of the present invention and those prepared using conventional single-tab plates. Figure 1 ;

[0042] Figure 12b This is a comparison of the temperature distribution of batteries prepared according to embodiments of the present invention and those prepared using conventional single-tab plates. Figure 2 ;

[0043] Figure 13 This is a schematic diagram showing the cycle performance of the 5-1# battery and the 4-4# battery of the present invention;

[0044] Figure 14This is a temperature distribution comparison diagram of the 5-1# battery and the 4-4# battery of the present invention.

[0045] Figure label:

[0046] 1-Frame, 2-Single tab, 31-First tab, 32-Second tab, 4-Rib, 41-First rib, 42-Second rib, 5-Positive busbar, 6-Positive terminal, 7-Negative busbar, 8-Negative terminal. Detailed Implementation

[0047] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0048] Existing lead-acid batteries with grid structures suffer from uneven current distribution within the plates, large ohmic voltage drop, short cycle life, or complex manufacturing processes. Therefore, the inventors conducted extensive research, investigating several typical grid structures and batteries, and comparing their performance in an effort to develop a high-performance lead-acid battery.

[0049] This invention provides a lead-acid battery, comprising a single cell, each cell including multiple positive plates and multiple negative plates alternately stacked; each positive plate and each negative plate includes a frame 1 and a tab, the frame 1 including an upper frame, a lower frame, a left frame, and a right frame; each positive plate and each negative plate includes a first tab 31 and a second tab 32, the first tab 31 and the second tab 32 being symmetrically arranged along the length of the upper frame; the plane containing the first tab 31 and the second tab 32 is parallel to the plate surface; in the positive plate, the distance between the first tab 31 and the second tab 32 is d1; in the negative plate, the distance between the first tab 31 and the second tab 32 is d2, d1 and d2 are different; in the positive plate, the first tab 32 and the second tab 32 are of the same size.

[0050] Specifically, in the negative electrode plate, the first tab 31 and the second tab 32 are the same size.

[0051] Compared with existing technologies, the lead-acid battery provided by this invention uses a bi-tab grid for both the positive and negative plates. By optimizing the tab structure, the tabs of the bi-tab grid are symmetrically located on the left and right sides of the upper frame, resulting in uniform current distribution across the entire plate surface and reduced potential loss. This reduces heat generation during high-current charging and discharging, which is beneficial for high-power operation and extends battery life.

[0052] Specifically, the length of the top border is L1, where L1 ≥ d1 > d2.

[0053] Specifically, in a single cell, the top of the tab of the positive plate is the positive busbar 5, and the top of the tab of the negative plate is the negative busbar 7. The tabs of each plate in the single cell are connected in parallel through the busbars. The tabs of each positive plate are connected to the positive terminal 6 through the positive busbar 5, and the tabs of each negative plate are connected to the negative terminal 8 through the negative busbar 7.

[0054] Specifically, in the positive electrode of a single cell, the top of the first tab is a first positive busbar, which connects multiple positive electrode first tabs together in parallel; the top of the second tab is a second positive busbar, which connects multiple positive electrode second tabs together in parallel; in the negative electrode of a single cell, the top of the first tab is a first negative busbar, which connects multiple negative electrode first tabs together in parallel; the top of the second tab is a second negative busbar, which connects multiple negative electrode second tabs together in parallel; the first tab of each positive electrode is connected to the positive terminal 6 through the first positive busbar, and the second tab of each positive electrode is connected to the positive terminal 6 through the second positive busbar; the first tab of each negative electrode is connected to the negative terminal 8 through the first negative busbar, and the second tab of each negative electrode is connected to the negative terminal 8 through the second negative busbar.

[0055] Specifically, in a single cell, the negative plate includes multiple horizontally and vertically intersecting ribs 4 within its frame. The ribs 4 include multiple first ribs 41 distributed horizontally along the plate surface and multiple second ribs 42 distributed vertically along the plate surface. The first ribs 41 and the second ribs 42 intersect perpendicularly.

[0056] Specifically, in a single cell, the frame of the positive plate includes multiple horizontal and vertical intersecting ribs 4. The ribs 4 include multiple first ribs 41 distributed horizontally along the surface of the plate and multiple second ribs 42 distributed vertically along the surface of the plate. The first ribs 41 and the second ribs 42 intersect perpendicularly.

[0057] Preferred, such as Figure 3b As shown, in the positive electrode plate, the ribs 4 include multiple first ribs 41 distributed laterally along the electrode plate surface and multiple second ribs 42 distributed longitudinally along the electrode plate surface. The second ribs 42 located on the vertical center line of the upper frame are rectangular and serve as reinforcing ribs, improving the creep resistance of the middle part of the electrode plate (once the electrode plate creeps, it will push against the busbar, causing a short circuit failure). The shape of the remaining second ribs 42 is such that the width of the second ribs 42 gradually decreases along the direction away from the upper frame, that is, it is thicker at the top and gradually thinner at the bottom. For example, the shape of the second ribs 42 is trapezoidal, with the side length near the upper frame being greater than the side length away from the electrode tab. The arrangement of the second ribs 42, which is thicker at the top and thinner at the bottom, is beneficial to the corrosion resistance and current collection function of the upper part.

[0058] Specifically, the difference between the upper and lower side lengths of the second rib 42 is 0.6 to 1.5 mm.

[0059] Preferably, in the positive electrode plate, each first rib 41 is V-shaped with its opening facing the upper frame. The V-shape of the first rib 41 can improve the creep resistance of the grid. For example, the included angle of the V-shape is greater than 90° and less than 180°.

[0060] Specifically, in the positive electrode plate, the distribution of the first rib 41 is such that the distance between two adjacent first ribs 41 is not exactly the same along the direction away from the upper frame.

[0061] Preferably, in the positive electrode plate, the distribution of the first ribs 41 is such that, along the direction away from the upper frame, the spacing between them gradually decreases from top to bottom. That is, the distribution of the first ribs 41 is sparse at the top and dense at the bottom. In other words, along the direction away from the upper frame, the distance between two adjacent first ribs 41 gradually decreases. This arrangement is beneficial to improving the utilization rate of the active material at the bottom of the electrode plate. For example, the distance between two adjacent first ribs 41 is 10-2 mm.

[0062] Considering that the reaction at the upper part of the electrode plate is more intense and the corrosion of the ribs is more severe, in order to reduce the corrosion of the ribs and reduce costs, it is preferable that the width of the first rib 41 in the positive electrode plate is not completely uniform.

[0063] In one possible design, along the direction away from the top edge, the width of the first ribs in the upper part is the same, and the width of the first ribs in the lower part is the same, with the width of the first ribs in the upper part being greater than the width of the first ribs in the lower part; for example, the number of the first ribs in the upper part accounts for 1 / 4 to 1 / 2 of the total number of the first ribs.

[0064] In one possible design, the width of the first rib gradually decreases along the direction away from the top edge.

[0065] Specifically, the dimensions of the first tab 31 and the second tab 32 are designed according to the specific battery model.

[0066] Specifically, the thickness of the first tab 31 and the second tab 32 is slightly less than the thickness of the frame 1, and the difference between the thickness of the frame 1 and the thickness of the first tab 31 and the second tab 32 is 0.5 to 3 mm.

[0067] It should be noted that, considering the high utilization rate of the positive plate in lead-acid batteries, to reduce costs, the thickness of the negative plate can be less than that of the positive plate, and the number of ribs on the negative plate can be less than that on the positive plate. This design can reduce production costs while maintaining battery performance, resulting in significant economic benefits.

[0068] Specifically, the thickness of the negative electrode plate can be 70% to 95% of the thickness of the positive electrode plate, and the number of ribs on the negative electrode plate can be 70% to 95% of the number of ribs on the positive electrode plate.

[0069] It should be noted that in a single cell, the design of the ribs and shape of the negative electrode plate can be the same as that of the positive electrode plate.

[0070] Specifically, the aforementioned lead-acid battery may include one or more individual cells. Each individual cell has a nominal voltage of 2.0V, can discharge to 1.7V, and can charge to 2.5V. In applications, six individual cells can be connected in series to form a lead-acid battery with a nominal voltage of 12V. Multiple individual cells can also be connected in series to form lead-acid batteries with nominal voltages of 24V, 36V, 48V, etc.

[0071] It should be noted that the aforementioned lead-acid batteries can be used as power batteries. Power batteries typically discharge at a rate of around 0.5C and are charged at around 0.25C. At this rate, the interaction between ion migration and the positive and negative plates is significant, requiring specific design for the tabs and rib arrangement.

[0072] The power battery of this invention differs from that of a car starting battery. Car starting batteries require instantaneous high current output capability. Therefore, in terms of the distribution of ribs on the positive plate, the main design principle is to minimize the internal resistance of the ribs. Generally, a radial rib distribution is adopted. Since the discharge time is extremely short, the interaction between the positive and negative electrodes during the discharge process through ion migration can be small. Therefore, the relative position of the positive and negative electrode tabs has a small impact.

[0073] The power battery of this invention differs from gel energy storage batteries. Gel energy storage batteries generally use low-rate discharge of less than 10 hours, and the ion migration rate has little impact on the interaction between the positive and negative electrodes. Therefore, the relative positions of the positive and negative electrodes are less affected.

[0074] Compared with existing technologies, the lead-acid battery of this invention optimizes the tab structure, with both positive and negative tabs symmetrically located on the left and right sides of the upper frame, resulting in uniform current distribution across the entire plate surface and reduced potential loss. This reduces heat generation during high-current charging and discharging, facilitating high-power operation and extending battery life. Furthermore, the lead-acid battery of this invention features a simple grid structure and a simple manufacturing process, making it suitable for mass production.

[0075] Furthermore, the bipolar tabs of the negative electrode plate of this invention further improve the power characteristics and promote a more uniform current distribution on the electrode plate during charging and discharging; the different positions of the tabs on the positive and negative electrodes are conducive to welding the busbar, the manufacturing process is simple, and it is suitable for large-scale production.

[0076] In the lead-acid battery of the present invention, the second rib on the vertical line of the upper frame of the electrode plate is rectangular, which serves as a reinforcing rib and can improve the creep resistance of the middle part of the electrode plate; the remaining second ribs are thicker at the top and thinner at the bottom, which can help the upper part resist corrosion and have a current collection function.

[0077] In the lead-acid battery of the present invention, the first rib is V-shaped, which can improve the creep resistance of the grid; the distribution of the first rib is sparse at the top and dense at the bottom, which is conducive to improving the utilization rate of the active material at the bottom of the plate; the upper part of the first rib is thicker and the lower part of the first rib is thinner, which can reduce the cost while reducing the corrosion of the rib.

[0078] The lead-acid battery of the present invention has a negative electrode plate with a thickness less than that of the positive electrode plate, and a negative electrode plate with fewer ribs than the positive electrode plate. This reduces production costs while ensuring battery performance, resulting in significant economic benefits.

[0079] To demonstrate the beneficial effects of the lead-acid battery of the present invention, the inventors compared several typical solutions developed during their research process, as described below.

[0080] Example 1

[0081] This embodiment provides a grid for lead-acid batteries (hereinafter referred to as grid), such as Figure 1 As shown, the grid includes a frame 1 and a tab. The frame 1 includes a top frame, a bottom frame, a left frame, and a right frame. There is one tab, referred to as a single tab 2, which is located in the middle of the top frame. The plane of the single tab 2 is parallel to the grid surface. The single tab 2 is 5mm wide and 10mm high. The thickness of the single tab 2 is slightly less than the thickness of the frame 1, and the difference between the thickness of the frame 1 and the thickness of the single tab 2 is 1mm.

[0082] The interior of the frame 1 is provided with multiple horizontal and vertical intersecting ribs 4. The ribs 4 include multiple first ribs 41 distributed horizontally along the direction of the electrode plate and multiple second ribs 42 distributed vertically along the direction of the electrode plate. The first ribs 41 and the second ribs 42 intersect perpendicularly.

[0083] Example 2

[0084] This embodiment provides a grid for a lead-acid battery, such as... Figure 2As shown, the grid includes a frame 1 and electrode tabs. The frame 1 includes an upper frame, a lower frame, a left frame, and a right frame. The electrode tabs include a first electrode tab 31 and a second electrode tab 32. Along the length of the upper frame of the grid, the first electrode tab 31 and the second electrode tab 32 are symmetrically arranged on the upper frame, and the plane containing the first electrode tab 31 and the second electrode tab 32 is parallel to the grid surface. The first electrode tab 31 and the second electrode tab 32 have the same dimensions, and the width of both the first electrode tab 31 and the second electrode tab 32 is 3mm. The distance between the first electrode tab 31 and the second electrode tab 32 is 7mm. The interior of the frame 1 is provided with multiple horizontally and vertically intersecting ribs 4. The ribs 4 include multiple first ribs 41 distributed horizontally along the electrode direction and multiple second ribs 42 distributed vertically along the electrode direction. The first ribs 41 and the second ribs 42 intersect perpendicularly.

[0085] Example 3

[0086] This embodiment provides a grid for a lead-acid battery, such as... Figure 3a As shown, the grid includes a frame 1 and electrode tabs. The frame 1 includes an upper frame, a lower frame, a left frame, and a right frame. The electrode tabs include a first electrode tab 31 and a second electrode tab 32. Along the length of the upper frame of the grid, the first electrode tab 31 and the second electrode tab 32 are symmetrically arranged on the outer side of the upper frame, and the plane containing the first electrode tab 31 and the second electrode tab 32 is parallel to the grid surface. The distance between the first electrode tab 31 and the second electrode tab 32 is d3, the width of the first electrode tab 31 is w2, and the length of the frame 1 is L, where L = d3 + 2w2. For example, w2 is 3mm, L is 66mm, and d3 is 60mm. Multiple ribs 4 are also provided within the frame 1. The ribs 4 include multiple first ribs 41 distributed laterally along the electrode surface and multiple second ribs 42 distributed longitudinally along the electrode surface. The first ribs 41 and the second ribs 42 intersect perpendicularly.

[0087] like Figure 3b As shown, in one possible design, multiple horizontally and vertically intersecting ribs 4 are also provided within the frame 1. The ribs 4 include multiple first ribs 41 distributed horizontally along the electrode surface and multiple second ribs 42 distributed vertically along the electrode surface. The second ribs 42 on the vertical axis of the upper frame are rectangular, serving as reinforcing ribs, while the remaining second ribs 42 are trapezoidal in shape, thicker at the top and thinner at the bottom. Each first rib 41 is V-shaped with a V-angle of 150°. The distribution of the first ribs 41 is sparse at the top and dense at the bottom (for example, the distances between two adjacent first ribs 41 are 9mm, 8.5mm, 8mm, 7.5mm, 7mm, 7.5mm, 6mm, 5mm, 4mm, and 3mm, respectively). The width of the first ribs in the upper part is the same, and the width of the first ribs in the lower part is the same, but the width of the first ribs in the upper part is greater than that in the lower part; the number of first ribs in the upper part accounts for 5 / 13 of the total number of first ribs.

[0088] Example 4

[0089] This embodiment provides a lead-acid battery, including a single cell, such as... Figure 4a As shown, a single cell includes multiple positive and negative plates stacked alternately. The negative plate of the lead-acid battery uses the type described in Example 3. Figure 3a The lead-acid battery uses the grid structure of Example 1 for its positive plate. In this example, a single cell consists of 4 positive plates and 5 negative plates connected in parallel. The tabs are the connection points of these plates; each plate conducts current through its own tab. The top of the tab of the positive plate is the positive busbar 5, and the top of the tab of the negative plate is the negative busbar 7. These busbars then connect the tabs of all the plates in the single cell in parallel. The number of plates can be either 4 positive plates and 5 negative plates, or 5 positive plates and 6 negative plates, depending on the battery capacity and model.

[0090] This embodiment uses the above-mentioned six individual battery cells connected in series to form a lead-acid battery with a nominal voltage of 12V. The tabs of each positive plate are connected to the positive terminal 6 via the positive busbar 5, and the tabs of each negative plate are connected to the negative terminal 8 via the negative busbar 7. The six individual battery cells can be connected in series in a 1×6 structure. Figure 4a (marked as 4-1#), 2×3 structure ( Figure 5 (marked as 4-2#) or 3×2 structure ( Figure 6 (marked as 4-3#).

[0091] It should be noted that, as Figure 4b As shown, in this embodiment, the positive plate of the lead-acid battery can also adopt the grid structure of Embodiment 3, and the negative plate of the lead-acid battery can adopt the grid structure of Embodiment 1. The six individual cells can be connected in series in a 1×6 structure. Figure 4b , marked as 4-4#, 2×3 structure (marked as 4-5#) or 3×2 structure (marked as 4-6#).

[0092] Example 5

[0093] This embodiment provides a lead-acid battery, including a single cell, such as... Figure 7a , 7b As shown, a single-cell battery includes multiple positive and negative plates stacked alternately, with the negative plate employing the method described in Example 3. Figure 3a The grid structure of the positive plate adopts the grid structure of Example 2. The single cell of this example consists of 4 positive plates and 5 negative plates connected in parallel. The tabs are the connection points of these plates. That is, each plate must conduct current through its own tab. The top of the tab of the positive plate is the positive busbar 5, and the top of the tab of the negative plate is the negative busbar 7. The tabs of each plate in the single cell are connected in parallel through the busbars.

[0094] This embodiment uses the above-mentioned six individual battery cells connected in series to form a lead-acid battery with a nominal voltage of 12V. The tabs of each positive plate are connected to the positive terminal 6 via the positive busbar 5, and the tabs of each negative plate are connected to the negative terminal 8 via the negative busbar 7. The six individual battery cells can be connected in series in a 1×6 structure. Figure 7a (marked as 5-1#), 2×3 structure (marked as 5-2#), or 3×2 structure ( Figure 9a (marked as 5-3#).

[0095] It should be noted that in this embodiment, the positive electrode plate of a single cell may also adopt the design of Embodiment 3. Figure 3a The grid structure of the single cell is as described in Example 2. The six single cells can be connected in series in a 1×6 structure. Figure 7b (marked as 5-4#), 2×3 structure ( Figure 8 (marked as 5-5#) or 3×2 structure ( Figure 9b (marked as 5-6#).

[0096] Example 6

[0097] This embodiment provides a lead-acid battery, including a single cell. Each cell comprises multiple positive and negative plates alternately stacked. The positive plate of the single cell uses the method described in Embodiment 3. Figure 3b The lead-acid battery uses the grid structure of Example 1 for its negative electrode plate. It should be noted that the lead-acid battery may include six individual cells, which can be connected in series in a 1×6 structure (marked as 6-1#), a 2×3 structure, or a 3×2 structure.

[0098] In this embodiment, the design of the ribs and shape of the negative electrode plate can be the same as that of the positive electrode plate.

[0099] Example 7

[0100] This embodiment provides a lead-acid battery, including a single cell. Each cell comprises multiple positive and negative plates alternately stacked. The positive plate of the single cell uses the method described in Embodiment 3. Figure 3b The grid structure of the single cell is as described in Example 2. It should be noted that the lead-acid battery may include six single cells, which can be connected in series in a 1×6 structure (marked as 7-1#), a 2×3 structure, or a 3×2 structure.

[0101] In this embodiment, the design of the ribs and shape of the negative electrode plate can be the same as that of the positive electrode plate.

[0102] like Figure 11The diagram shows the cycle performance of the battery. In the diagram, 1# represents a 1×6 battery made with a conventional single-tab electrode plate (e.g., ...). Figure 10 As shown in the diagram, #2 is a 1×6 battery structure of #4-4. All other aspects remain the same, and the cells are cycled. The diagram shows that the cycle performance of #4-4 is superior to that of traditional single-tab batteries.

[0103] like Figure 12a , 12b The diagram shows the temperature distribution of the battery. Figure 12a In the middle, the left figure is a schematic diagram of the battery prepared by the traditional single-tab electrode plate, and the right figure is a schematic diagram of the battery 5-1#. Figure 12b The left figure shows the result of a battery prepared with a traditional single-tab electrode plate, and the right figure shows the result of battery 4-4#. Analysis of the temperature distribution in the figures shows that, compared to batteries prepared with traditional single-tab electrodes, the battery of this invention, with both positive and negative electrodes having double tabs, exhibits a more uniform current distribution on the plate surface, generates less heat, and has better temperature uniformity, which is beneficial for improving battery cycle performance.

[0104] like Figure 13 The diagram shows the cycle performance of the battery. In the diagram, A represents a 5-1# battery structure where both the positive and negative plates have bitabs (e.g., ...). Figure 7a As shown), B is the positive electrode with a bipolar tab and the negative electrode with a unipolar tab, 4-4# (as shown). Figure 4b The diagram shows a 1×6 battery structure. All other aspects remain the same, and the battery is cycled. As can be seen from the diagram, the A battery of this invention (a battery structure with both positive and negative plates having bitabs) has a higher discharge capacity and a higher number of cycles. It is evident that the cycle performance of a battery with both positive and negative plates having bitabs is superior to a battery with one positive plate having a bitab and the other a unitab.

[0105] like Figure 14 The diagram shown illustrates the temperature distribution of the battery. Figure 14 In the diagram, the left image shows the result for battery B, and the right image shows the result for battery A. Analyzing the temperature distribution in the images, under the same current and other conditions, battery A's temperature is slightly lower than battery B's. Battery A has a more uniform current distribution on its plates, generates less heat, and has better temperature uniformity, which is beneficial for improving battery cycle performance.

[0106] The performance data of batteries prepared with conventional single-tab plates, battery 4-4# of Example 4, battery 6-1# of Example 6, battery 5-4# of Example 5, and battery 7-1# of Example 7 are listed in Table 1 below. It can be seen that the performance of the batteries of the present invention is significantly better than that of batteries prepared with conventional single-tab plates. Battery 5-4# of the present invention outperforms battery 4-4#, battery 7-1# outperforms battery 6-1#, battery 6-1# outperforms battery 4-4#, and battery 7-1# outperforms battery 5-4#. It is evident that the cycle performance of the battery of the present invention, where both the positive and negative plates are bitabs, is better than that of the battery where one positive plate is bitabated and the other is single-tabped; the bitabs on the negative plate further improve the power characteristics. In the present invention, optimizing the shape and position distribution of the ribs on the positive plate can further improve the battery performance. Specifically, in the positive electrode plate, the second rib on the vertical line of the upper frame is rectangular, serving as a reinforcing rib and improving the creep resistance of the middle part of the plate; the remaining second ribs are thicker at the top and thinner at the bottom, which is beneficial for the corrosion resistance and current collection effect of the upper part. In the positive electrode plate, the first rib is V-shaped, which can improve the creep resistance of the grid; the distribution of the first ribs is sparse at the top and dense at the bottom, which is beneficial for improving the utilization rate of the active material at the bottom of the plate; the thicker first ribs in the upper part and the thinner first ribs in the lower part can reduce costs while reducing the corrosion of the ribs.

[0107] Table 1 Performance data of different batteries

[0108]

[0109]

[0110] Note: The improvements in active material utilization and power characteristics mentioned in the table refer to the comparison with batteries made using traditional single-tab plates.

[0111] It should be noted that, in order to reduce costs, the inventors reduced the thickness of the negative electrode plate of the 5-1# battery structure by 10% and the number of ribs by 6%. The cycle performance of the battery is comparable to that of the 5-1# battery, and the cost is reduced by more than 15%.

[0112] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A lead-acid battery suitable for power batteries, characterized in that, The lead-acid battery includes a single cell, which includes multiple positive plates and multiple negative plates arranged alternately; each positive plate and each negative plate includes a frame (1) and a tab, and the frame (1) includes an upper frame, a lower frame, a left frame and a right frame; Each positive electrode plate and each negative electrode plate has a first electrode tab (31) and a second electrode tab (32). The first electrode tab (31) and the second electrode tab (32) are symmetrically arranged on the upper frame along the length direction of the upper frame. The plane containing the first electrode tab (31) and the second electrode tab (32) is parallel to the electrode plate surface. In the positive electrode plate, the distance between the first electrode tab (31) and the second electrode tab (32) is d1. In the negative electrode plate, the distance between the first electrode tab (31) and the second electrode tab (32) is d2. d1 and d2 are different. In the positive electrode plate, the first electrode tab (31) and the second electrode tab (32) have the same size. Multiple ribs (4) are also provided inside the frame (1); The ribs include multiple first ribs distributed laterally along the electrode plate surface and multiple second ribs distributed longitudinally along the electrode plate surface; the second ribs located on the vertical line of the upper frame are rectangular, and the shape of the remaining second ribs is such that the width of the second ribs gradually decreases along the direction away from the upper frame. The first ribs are all V-shaped, with the opening facing the upper frame; Distribution of the first ribs: Along the direction away from the top border, the distance between two adjacent first ribs gradually decreases; Along the direction away from the top edge, the width of the first rib in the upper part is the same, and the width of the first rib in the lower part is the same. The width of the first rib in the upper part is greater than the width of the first rib in the lower part. The number of the first ribs in the upper part accounts for 1 / 4 to 1 / 2 of the total number of the first ribs.

2. The lead-acid battery according to claim 1, characterized in that, In the negative electrode plate, the first tab (31) and the second tab (32) are the same size.

3. The lead-acid battery according to claim 2, characterized in that, The length of the upper border is L1, where L1 ≥ d1 > d2.

4. The lead-acid battery according to claim 2, characterized in that, The length of the upper border is L1, where L1≥d2>d1.

5. The lead-acid battery according to claim 1, characterized in that, In the positive electrode plate of the single cell, the top of the first tab is the first positive busbar, which connects multiple positive electrode plates with their first tabs in parallel; the top of the second tab is the second positive busbar, which connects multiple positive electrode plates with their second tabs in parallel. In the negative electrode plate of the single cell, the top of the first tab is the first negative busbar, which connects the first tabs of multiple negative electrode plates in parallel; the top of the second tab is the second negative busbar, which connects the second tabs of multiple negative electrode plates in parallel.

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