Negative plate for lead-acid storage battery

Abstract

The invention discloses a negative plate for a lead-acid storage battery, and relates to the technical field of storage batteries, the using amount of a negative plate alloy is 1.95-2.47 g / Ah, the using amount of the negative plate alloy is 0.665-0.845 g / cm < 3 >, the using amount of a negative plate active substance is 9.7-12.9 g / Ah, and the using amount of the negative plate active substance is 3.327-4.402 g / cm < 3 >. The negative plate comprises a negative plate grid and a negative plate active substance, the structure of the negative plate is optimally designed, a large-area plate structure is adopted, so that the alloy consumption can be greatly reduced, and the contact resistance between the surface of the plate grid and the active substance is small and the conductivity is good through the process treatment of acid pickling, spraying of graphene-containing suspension and the like on the surface of the plate grid.

Description

Technical Field

[0001] The present invention relates to the technical field of storage batteries, and particularly to a negative plate for a lead-acid storage battery. Background Art

[0002] With the change of market demand, the lightweight and high specific energy design of electric bicycle batteries are the main research and development directions of power lead-acid batteries. The stamped grid has strong corrosion resistance, long service life, and low cost. With the help of stamping dies and high-speed punching presses, the grid can be continuously mass-produced, and there is no pollution such as lead smoke and lead dust during the grid production process. Currently, the power lead-acid battery plates used in electric bicycles on the market are basically stamped plates. However, to meet the requirements of lightweight batteries with high weight specific energy and reduce the consumption of lead, optimizing the plate design is the key while ensuring the battery performance does not decrease.

[0003] Therefore, in the prior art, many solutions have been proposed to optimize the plates. For example, a positive plate proposed in the prior art EP22947448 provides a method for preparing a positive plate and a positive plate, a secondary battery, and an electrical device including the same. The positive electrode material composition of this patented technology enables the secondary battery to have a higher energy density, and at the same time has improved cycle performance, safety performance, and / or rate performance. However, the focus of this technical solution is on the preparation materials of the positive plate. Another example is the prior art DE102023126989A1, which proposes a mixed openwork cloth / paste paper material for a plate-type storage battery electrode for a lead-acid storage battery, especially for a positive plate-type storage battery electrode for a lead-acid storage battery, where the openwork cloth / paste paper material is made in the form of a non-woven fabric mat or a woven fabric mat. The improvement of this technology for the positive plate also focuses on the manufacturing or material aspects.

[0004] It can be seen that the prior art optimization solutions for the plates mostly focus on the manufacturing aspect, and some technologies focus on other aspects. For example, in the prior art JP2025039251A, a liquid lead storage battery is proposed, which includes an electrode plate group, an electrolyte, and a battery chamber for accommodating the electrode plate group and the electrolyte. The electrode plate group includes a positive electrode plate, a negative electrode plate, and a separator disposed between the positive electrode plate and the negative electrode plate. The difference between the sum s of the distances between the positive and negative electrode plates facing each other in the plate group and the sum t of the thicknesses of the separators: (s - t) is 0.10 mm or less. It can be seen that this technology focuses on the optimization of the distance between the positive and negative electrode plates. Another example is the prior art JP2025032525A, which provides a lead storage battery and a manufacturing method thereof that can further increase the capacitance while maintaining or increasing the yield. The lead storage battery is a lead storage battery with a negative electrode plate, and the negative electrode plate has a lead alloy grid body, and the thickness of the grid body is 1.6 mm or more and 2.9 mm or less. This technical means focuses on the yield of the plates. Summary of the Invention

[0005] The object of the present invention is to provide a negative plate for a lead-acid battery, optimize the design of the negative plate structure, adopt a large-area plate structure, effectively reduce the number of negative plates configured in a single battery, and the solution of the present invention can enable the manufactured battery to maintain a more uniform electrochemical reaction during charge and discharge.

[0006] To solve the above technical problems, the present invention specifically provides the following technical solutions: A negative plate for a lead-acid battery, the alloy consumption of the negative plate is 1.95 - 2.47 g / Ah; the alloy consumption of the negative plate is 0.665 - 0.845 g / cm 3 ; the negative plate includes a negative grid and negative plate active material; the amount of negative plate active material is 3.327 - 4.402 g / cm 3 ; the amount of negative plate active material is 9.7 - 12.9 g / Ah.

[0007] The negative plate of the present invention is an extended plate configuration. Compared with the existing plates, while maintaining the same external dimensions, the battery capacity is increased, so that the capacity of a single negative plate reaches 6.67 Ah, which is 66.75% higher than the capacity of 4 Ah of the traditional design negative plate. After the plate surface size of the present invention is enlarged, the current transmission path is shortened, the internal resistance is reduced by 15 - 20%, the number of connection points is reduced due to the reduction of the number of plates, the reliability is improved, and the further reduction of the number of plates further reduces the internal resistance, realizing the reduction of lead material consumption while maintaining the battery discharge performance and cycle life.

[0008] For a battery prepared with the negative plate of the present invention, such as a battery with a capacity of 20 Ah, 2 positive plates and 3 negative plates are used. The capacity of the positive plate = 20 Ah / 2 = 10 Ah, and the capacity of the negative plate = 20 Ah / 3 = 6.67 Ah.

[0009] Calculation method of plate capacity: Refer to the national standard GB / T 22199.1 - 2017 "Valve-regulated lead-acid batteries for electric assist bicycles - Part 1: Technical conditions", the capacity is the 2-hour rate capacity, and the plate capacity = capacity / number of plates in a single cell.

[0010] According to an embodiment of the present invention, the negative plate includes at least one negative grid with a tab, which simplifies the plate assembly process and improves the production yield.

[0011] According to an embodiment of the present invention, the negative electrode plate active material is lead paste, and the lead paste contains a two-dimensional conductive material and glass nanotubes. The addition of the two-dimensional conductive material constructs an efficient three-dimensional conductive network, greatly reducing the internal resistance of the electrode plate, promoting electron transport, and making the redox reactions of active materials such as PbSO4 and Pb more sufficient. Under the same discharge capacity requirement, the amount of active material can be reduced, thereby reducing the weight of the electrode plate and increasing the energy density of the battery. The porous structure of the glass nanotubes can serve as a micron-level electrolyte channel, quickly replenishing sulfuric acid electrolyte during discharge and effectively alleviating the concentration polarization phenomenon caused by the lag of electrolyte diffusion on the electrode plate surface. This characteristic significantly improves the voltage stability during high-rate discharge and reduces the ineffective energy loss. The synergistic effect of the two-dimensional conductive material and the glass nanotubes not only ensures the electron conduction efficiency but also optimizes the ion transport path, enabling the electrode plate to maintain a more uniform electrochemical reaction during charge and discharge.

[0012] According to an embodiment of the present invention, the negative grid of the present invention is surface-treated, and the surface treatment process method is as follows: 1.1 Multi-pass rolling process The grid is made by subjecting a lead plate about 15 mm thick to 7 - 9 passes of rolling process. Due to the multi-pass rolling process treatment of the grid, the density and strength of the alloy are very high, and the corrosion resistance is strong. Less grid alloy can be used to meet the usage requirements during the battery life cycle. Then, the rolled grid is heat-treated at a high temperature of 80 °C - 90 °C for 12 - 24 hours, and the hardness of the grid is greatly improved, which is convenient for improving the coating efficiency and qualification rate.

[0013] The thickness of the grid obtained by the multi-pass rolling process reaches 0.3 - 0.6 mm.

[0014] The present invention uses the rolling process treatment to be able to greatly improve the density and strength of the alloy and has strong corrosion resistance.

[0015] 1.2 Grid surface pickling treatment process After multi-pass rolling and high-temperature heat treatment, the surface structure of the grid is dense and has strong corrosion resistance. However, the oil film on the grid surface will cause a poor bonding force between the grid and the active material, and cleaning treatment is required. The grid is ultrasonically oscillated and cleaned with a weakly acidic solution (such as citric acid, lactic acid solution), and then the cleaned grid is quickly dried at a temperature of 80 - 90 °C to obtain the negative grid.

[0016] 1.3 Grid surface spraying process The pickled negative grid is then sprayed with a uniform graphene suspension on the surface of the negative grid, and then the grid is subjected to high-temperature rapid drying treatment, and the oven temperature is 90 - 120 °C. The negative grid sprayed with the graphene suspension has a strong bonding force with the active material, improves conductivity, and has a small interfacial resistance between the active material and the negative grid.

[0017] 1) Principle: Physical barrier effect: The graphene coating acts as a dense barrier, reducing the direct contact between the electrolyte and lead, and inhibiting the irreversible deposition of lead sulfate.

[0018] Electrochemical synergy: The conductive network of graphene promotes the rapid transmission of electrons, accelerating the reduction reaction of PbSO4→Pb. The reaction formula is as follows:

[0019] Enhancement of porous structure: The specific surface area of graphene (2630 m 2 / g) provides more reaction sites, enhancing the infiltration of the electrolyte and ion transport.

[0020] 2) Main functions Inhibition of sulfation: The graphene coating can prevent the lead sulfate (PbSO4) crystals from forming large crystals on the surface of the negative electrode, keeping them in a fine particle state, so that they are more easily dissolved back into active lead (Pb) during charging, significantly extending the cycle life.

[0021] Enhancement of conductivity: The high conductivity of graphene (electron mobility up to 15000 cm 2 / (V·s)) reduces the internal resistance of the negative electrode, improves the charge-discharge efficiency, especially the fast charging ability.

[0022] Stabilization of the electrode structure: The porous network structure of graphene supports the active material (sponge lead), preventing the active material from falling off during the charge-discharge process, and improving the mechanical strength and cycle stability.

[0023] According to an embodiment of the present invention, the negative grid is composed of a rectangular frame and internal reinforcing ribs. The frame includes two horizontally arranged horizontal frames and two vertically arranged vertical frames, jointly forming a closed frame. Inside the frame, there is a network of criss-crossing reinforcing ribs. The horizontal ribs are arranged in parallel at equal intervals and are respectively welded and fixed to the two vertical frames at both ends. The vertical ribs are arranged in parallel at equal intervals, and the number is significantly more than that of the horizontal ribs. The two ends are respectively welded and fixed to the two horizontal frames. The pole ear, as a current conduction component, extends vertically outward from the middle of one of the horizontal frames. The intersections of all the horizontal ribs and vertical ribs and the edges of the rib strips are chamfered to eliminate stress concentration and improve the structural reliability.

[0024] The criss-crossed horizontal and vertical ribs with equal spacing form a uniform grid support. In combination with the rectangular frame of the border, it effectively enhances the anti-deformation ability of the grid, reduces the stress damage during the charge and discharge cycle, extends the service life. The densely distributed vertical ribs, with a quantity more than that of the horizontal ribs, shorten the current conduction path, reduce the internal resistance. At the same time, the longitudinal extension design of the tab further reduces the current collection impedance and improves the charge and discharge efficiency. The equal-spacing arrangement and chamfer treatment of the rib strips expand the effective area of the electrode reaction, avoid local stress concentration, prevent the shedding of the active material, ensure the capacity retention rate. The chamfer structure reduces the burr risk during stamping or casting, improves the production yield, and at the same time facilitates the uniform filling of the lead paste in the pasting process, improving the electrode consistency.

[0025] A single cell, and the single cell includes a positive plate, a negative plate and a separator.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows: The negative plate of the present invention is an extended plate configuration. Compared with the existing plates with the same external dimensions, the battery capacity is increased, and the capacity of a single negative plate reaches 6.67 Ah, which is 66.75% higher than the capacity of 4 Ah of the traditional design negative plate. The present invention optimizes the design of the negative plate structure, adopts a large-area plate structure, while reducing the lead material usage, maintains the battery discharge performance and cycle life, and effectively reduces the configuration quantity of the negative plates in the single cell. Description of the Drawings

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only exemplary, and for those of ordinary skill in the art, without creative efforts, other implementation drawings can also be obtained according to the provided drawings.

[0028] Figure 1 Schematic diagram of a negative plate for a lead-acid battery of the present invention; Figure 2 Schematic diagram of the negative grid solution in the negative plate of the present invention; Figure 3 Another perspective schematic diagram of the negative grid in the negative plate of the present invention; Figure 4 Schematic diagram of the connection solution of the vertical and horizontal ribs of the present invention; Figure 5 Schematic diagram of a single-core battery prepared with the negative electrode plate of the present invention; Figure 6 Schematic diagram of a corrosion layer with high internal resistance formed on the grid surface during the plate curing and battery forming processes; Figure 7 Metallographic diagram of the grid without rolling treatment in Example 3; Figure 8 It is the metallographic diagram of the grid plate in Example 3 after 7 - 9 rolling processes; Figure 9 It is the SEM diagram of the negative grid plate in Example 3 without graphene spraying treatment; Figure 10 It is the SEM diagram of the negative grid plate in Example 3 after graphene spraying treatment.

[0029] Explanation of reference numerals: 10. Negative plate; 20. Terminal post; 30. Negative grid plate; 31. Ear; 32. Vertical rib; 33. Frame; 34. Horizontal rib; 40. Encapsulation bag; 50. Main body; 51. Insert; 52. Chuck; 60. Lead paste part; 61. Active material aggregation layer; 62. Corrosion layer; 63. Grid plate rib part. Detailed implementation manners

[0030] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0031] First, the concepts involved in the present application will be described in conjunction with the accompanying drawings. It should be noted here that the following descriptions of each concept are only for making the content of the present application easier to understand, and do not represent a limitation on the protection scope of the present application; at the same time, without conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0032] Example 1: A negative plate for a lead - acid battery, the alloy consumption of the negative plate is 1.95 - 2.47 g / Ah; the alloy consumption of the negative plate is 0.665 - 0.845 g / cm 3 ; the negative plate includes a negative grid plate and negative - plate active material; the amount of negative - plate active material is 3.327 - 4.402 g / cm 3 ; the amount of negative - plate active material is 9.7 - 12.9 g / Ah.

[0033] The negative electrode plate 10 of the present invention has an extended plate configuration. Compared with the existing plates, while maintaining the same external dimensions, the battery capacity is increased, so that the capacity of a single negative electrode plate reaches 6.67 Ah, which is 66.75% higher than the capacity of the negative electrode plate of the traditional design (4 Ah). After the plate surface size of the negative electrode plate of the present invention is enlarged, the current transmission path is shortened, the internal resistance is reduced by 15-20%, the number of connection points is reduced by reducing the number of plates, the reliability is improved, and further reduction of the internal resistance follows with the reduction of the number of plates, realizing the maintenance of the battery discharge performance and cycle life while reducing the lead material consumption.

[0034] The alloy consumption of the negative electrode plate is 1.95 - 2.47 g / Ah, and specifically, it can be selected as one of the following specific values or within the range between any two of them: 1.95, 1.96, 1.97, 1.98... 2.40, 2.41, 2.42, 2.43, 2.44, 2.45, 2.46, 2.47.

[0035] The alloy consumption of the negative electrode plate is 0.665 - 0.845 g / cm 3 , and specifically, it can be selected as one of the following specific values or within the range between any two of them: 0.665, 0.666, 0.667, 0.6668... 0.839, 0.840, 0.841, 0.842, 0.843, 0.844, 0.845.

[0036] The active material consumption of the negative electrode plate is 3.327 - 4.402 g / cm 3 , and specifically, it can be selected as one of the following specific values or within the range between any two of them: 3.327, 3.328, 3.329, 3.330, 3.331... 4.397, 4.398, 4.399, 4.400, 4.401, 4.402.

[0037] The active material consumption of the negative electrode plate is 9.7 - 12.9 g / Ah, and specifically, it can be selected as one of the following specific values or within the range between any two of them: 9.7, 9.8, 9.9, 10.0, 10.1... 12.4, 12.5, 12.6, 12.7, 12.8, 12.9.

[0038] The negative electrode plate 10 includes at least one negative plate grid 30 with a tab 31, which simplifies the plate assembly process and improves the production yield.

[0039] The negative electrode active material is lead paste, which contains two-dimensional conductive materials and glass nanotubes. The addition of two-dimensional conductive materials constructs an efficient three-dimensional conductive network, significantly reducing the internal resistance of the electrode plate, promoting electron transport, and making the redox reactions of active materials such as PbSO4 and Pb more complete. Under the same discharge capacity requirement, the amount of active material can be reduced, thereby reducing the weight of the electrode plate and increasing the energy density of the battery. The porous structure of the glass nanotubes can serve as a micron-level electrolyte channel, quickly replenishing sulfuric acid electrolyte during discharge, effectively alleviating the concentration polarization phenomenon caused by the lag of electrolyte diffusion on the electrode plate surface. This characteristic significantly improves the voltage stability during high-rate discharge and reduces the ineffective energy loss. The synergistic effect of two-dimensional conductive materials and glass nanotubes not only ensures the electron conduction efficiency but also optimizes the ion transport path, enabling the electrode plate to maintain a more uniform electrochemical reaction during charge and discharge.

[0040] The lead paste in this embodiment is prepared by mixing lead powder, water, sulfuric acid, and additives. The additives are two-dimensional conductive materials and glass nanotubes.

[0041] The negative grid 30 is composed of a rectangular frame 33 and internal reinforcing ribs. The frame 33 includes two horizontally arranged cross frames and two vertically arranged longitudinal frames, jointly forming a closed frame. Inside the frame, there is a network of crisscrossing reinforcing ribs. The horizontal ribs 34 are arranged in parallel at equal intervals and are welded and fixed to the two longitudinal frames at both ends respectively. The vertical ribs 32 are arranged in parallel at equal intervals, and the number is significantly more than that of the horizontal ribs 34. The two ends are welded and fixed to the two cross frames respectively. The tab 31, as a current conduction component, extends vertically outward from the middle of one of the cross frames. The intersections of all the horizontal ribs 34 and vertical ribs 32 and the edges of the rib strips are chamfered to eliminate stress concentration and improve the structural reliability.

[0042] The crisscrossing horizontal ribs 34 and vertical ribs 32 arranged at equal intervals form a uniform grid support. Combined with the rectangular frame of the frame 33, it effectively enhances the anti-deformation ability of the grid, reduces the stress damage during the charge and discharge cycle, and extends the service life. The densely distributed vertical ribs 32, with a number more than that of the horizontal ribs 34, shorten the current conduction path, reduce the internal resistance. At the same time, the longitudinal extension design of the tab 31 further reduces the current collection impedance and improves the charge and discharge efficiency. The equal-spacing arrangement and chamfering of the rib strips expand the effective area of the electrode reaction, avoid local stress concentration, prevent the shedding of active materials, ensure the capacity retention rate. The chamfered structure reduces the risk of burrs during stamping or casting, improves the production yield, and at the same time facilitates the uniform filling of lead paste in the pasting process and improves the electrode consistency.

[0043] A single cell, which includes a negative electrode plate 10, a positive electrode plate, and a separator.

[0044] Example 2: In this embodiment, the negative electrode plate 10 of the present invention adopts a large plate surface structure. Using the electrode plates with large plate surfaces reduces the number of positive and negative electrode plates used in the components of the single cell. The plate surface size of a single negative electrode plate is 148 mm × 132 mm, and the size of the existing electrode plates is 140 mm × 66 mm. The area is approximately twice that of the lead-acid battery electrode plates of ordinary electric bicycles on the market. The negative electrode plate 10 is provided with a pole column 20, and the thickness of the negative electrode plate 10 is about 1.0 mm.

[0045] In this embodiment, the parameters of the positive and negative electrode plates are as follows: Positive electrode plate: The weight of a single positive grid: 20 - 30 g; the weight of the single positive active material: 150 - 165 g; the capacity of a single positive electrode plate: 10 Ah; the alloy consumption: 2.0 - 3.0 g / Ah. This alloy consumption is reduced by about 37.5% compared with the alloy consumption of the existing single positive electrode plates; the consumption of the active material: 15.0 - 16.5 g / Ah, which is reduced by about 9.64% compared with the existing positive electrode plates.

[0046] Negative electrode plate: The weight of a single negative grid: 13 - 16.5 g; the weight of the single negative active material: 65 - 86 g; the capacity of a single negative electrode plate: 6.67 Ah; the alloy consumption: 1.95 - 2.47 g / Ah. This alloy consumption is reduced by about 29.1% compared with the alloy consumption of the existing single negative electrode plates; the consumption of the active material: 9.7 - 12.9 g / Ah, which is reduced by about 33.1% compared with the existing negative electrode plates.

[0047] In this embodiment, the configuration scheme of the single cell electrode plates is as follows: Number of positive electrode plates: 2 pieces, total alloy weight: 40 - 60 g, total active material weight: 300 - 330 g.

[0048] Number of negative electrode plates: 3 pieces, total alloy weight: 39 - 49.5 g, total active material weight: 195 - 258 g.

[0049] The number of positive electrode plates used in the single cell of the present invention is 2 pieces, and the number of negative electrode plates used is 3 pieces. Compared with the scheme of the existing technology that the single cell needs to use 4 positive electrode plates and 5 negative electrode plates, the scheme of the present invention optimizes the size structure of the positive and negative electrode plates, reduces the number of positive and negative electrode plates, realizes the light weight of the single cell, reduces the internal resistance, improves the assembly efficiency and ensures the battery performance.

[0050] The comparison between the single cell scheme made with the negative electrode plate of the present invention and the existing battery is shown in Table 1.

[0051] Table 1

[0052] Note: The calculation method of the plate capacity: Refer to the national standard GB / T 22199.1-2017 "Valve-regulated lead-acid batteries for electric assist bicycles - Part 1: Technical conditions". The capacity is the 2-hour rate capacity, and the plate capacity = capacity / number of plates per cell.

[0053] For the power batteries currently on the market, for a battery with a capacity of 20 Ah, 4 positive plates and 5 negative plates are used. The capacity of the positive plate = 20 Ah / 4 = 5 Ah, and the capacity of the negative plate = 20 Ah / 5 = 4 Ah; for the battery prepared with the negative plate of the present invention, if the capacity is 20 Ah, 2 positive plates and 3 negative plates are used. The capacity of the positive plate = 20 Ah / 2 = 10 Ah, and the capacity of the negative plate = 20 Ah / 3 = 6.67 Ah.

[0054] From the content of Table 1 above, it can be seen that the solution in this aspect significantly reduces the amount of alloy and active material per unit capacity through the large plate surface design. The amount of alloy used in the negative plate is reduced by about 29.1% g / Ah, and the negative active material is reduced by 33.1%. The number of plates used in the present invention is reduced. The positive electrode is reduced from 4 plates to 2 plates, and the negative electrode is reduced from 5 plates to 3 plates, reducing the internal resistance and improving the assembly efficiency. The solution of the present invention realizes the increase of the capacity of a single negative plate from 4 Ah to 6.67 Ah, and at the same time optimizes the material distribution to ensure a high energy density.

[0055] The length of the plate surface size of a single negative plate in this embodiment includes but is not limited to 148 mm, and can also be 60 mm, 60.1 mm, 60.2 mm... 65 mm, 65.1 mm, 65.2 mm, 65.3 mm... 75 mm, 75.1 mm, 75.2 mm, 75.3 mm, 75.4 mm,... 90 mm, 90.1 mm, 90.2 mm, 90.3 mm, 90.4 mm, 90.5 mm, 90.6 mm... 120 mm, 120.1 mm, 120.2 mm, 120.3 mm, 120.4 mm, 120.5 mm, 120.6 mm, 120.7 mm... 148 mm, 148.1 mm, 148.2 mm, 148.3 mm, 148.4 mm, 148.5 mm, 148.6 mm, 148.7 mm, 148.8 mm... 200 mm.

[0056] The width of the plate surface of the single negative plate in this embodiment includes, but is not limited to, 132 mm, and can also be 60 mm, 60.1 mm, 60.2 mm... 65 mm, 65.1 mm, 65.2 mm, 65.3 mm... 75 mm, 75.1 mm, 75.2 mm, 75.3 mm, 75.4 mm,... 90 mm, 90.1 mm, 90.2 mm, 90.3 mm, 90.4 mm, 90.5 mm, 90.6 mm... 120 mm, 120.1 mm, 120.2 mm, 120.3 mm, 120.4 mm, 120.5 mm, 120.6 mm, 120.7 mm... 148 mm, 148.1 mm, 148.2 mm, 148.3 mm, 148.4 mm, 148.5 mm, 148.6 mm, 148.7 mm, 148.8 mm... 200 mm.

[0057] Example 3: See the appendix Figure 6 As shown, between the grid rib part 63 and the active material aggregation layer 61 is the corrosion layer 62, and outside the active material aggregation layer 61 is the paste part 60. During the plate curing and battery formation processes, a corrosion layer with a high internal resistance is likely to form on the grid surface, increasing the battery internal resistance, resulting in a decrease in battery capacity and a shortening of the battery life.

[0058] During plate curing, a corrosion layer 62 of a mixture of PbO and Pb(OH)2 is formed on the grid surface.

[0059] During plate curing, a corrosion layer 62 is formed on the grid surface. At the beginning, the corrosion layer is very thin, and as the curing time prolongs, oxygen diffuses through the corrosion layer to continuously oxidize the grid rib part 63 of the grid matrix, and the corrosion layer 62 gradually thickens. During battery formation, oxygen passes through the corrosion layer 62 into the grid surface, and Pb on the grid surface is oxidized to PbO, and the generated PbO has a very high internal resistance. PbO is continuously oxidized to PbO n (1 < n < 2), and then oxidized to PbO2. If the generation rate of PbO is higher than the rate of further oxidation to PbO2, a high-resistance PbO layer will be formed on the grid surface, resulting in a decrease in battery capacity.

[0060] Therefore, the negative grid 30 of the present invention is surface-treated, and the surface treatment process method is as follows: 1.1 Multi-pass rolling process The grid is made by subjecting a lead plate about 15 mm thick to 7 - 9 rolling processes. Due to the multi - rolling process treatment of the grid, the density and strength of the alloy are very high, and the corrosion resistance is strong. Therefore, a relatively small amount of grid alloy is sufficient to meet the usage requirements during the battery life cycle. Then, the rolled grid is heat - treated at a high temperature of 80°C - 90°C for 12 - 24 hours. The hardness of the grid is greatly improved, which is convenient for improving the efficiency and qualification rate of paste - coating.

[0061] The thickness of the grid obtained by multi - rolling process treatment reaches 0.3 - 0.6 mm.

[0062] The rolling process treatment adopted in the present invention can improve the density and strength of the alloy, and the corrosion resistance is strong. Refer to the Figure 7 metallographic diagram of the grid without rolling treatment and the Figure 8 metallographic diagram of the grid after 7 - 9 rolling processes as shown. It can be seen that after 7 - 9 rolling processes, the density of the grid alloy is increased and its surface structure is dense.

[0063] 1.2 Grid surface pickling treatment process After multi - rolling and high - temperature heat treatment, the surface structure of the grid is dense and the corrosion resistance is strong. However, the oil film on the grid surface will result in a poor bonding force between the grid and the active material, so cleaning treatment is required. The grid is ultrasonically cleaned at a high frequency in a weakly acidic solution (such as citric acid, lactic acid solution), and then the cleaned grid is quickly dried at a temperature of 80 - 90°C to obtain the negative grid.

[0064] 1.3 Grid surface spraying process The pickled negative grid is then sprayed with a uniform graphene suspension on its surface, and then the grid is subjected to high - temperature rapid drying treatment, with the oven temperature being 90 - 120°C. The negative grid sprayed with the graphene suspension has a strong bonding force with the active material, improves conductivity, and has a small interfacial resistance between the active material and the negative grid.

[0065] The mass percentage of the graphene suspension is 0.1 - 0.4%. The components of the graphene suspension are: graphene nanosheets, water; the spraying speed is 10 - 30 m / min.

[0066] 1) Principle: Physical barrier effect: The graphene coating acts as a dense barrier, reducing the direct contact between the electrolyte and lead, and inhibiting the irreversible deposition of lead sulfate.

[0067] Electrochemical synergy: The conductive network of graphene promotes the rapid transmission of electrons, accelerating the reduction reaction of PbSO4→Pb. The reaction formula is as follows:

[0068] Enhanced Porous Structure: The specific surface area of graphene (2630 m 2 / g) provides more reaction sites, enhancing electrolyte infiltration and ion transport.

[0069] 2) Main Functions Inhibition of Sulfation: The graphene coating can prevent lead sulfate (PbSO4) crystals from forming large crystals on the negative electrode surface, keeping them in a fine particle state, making it easier to dissolve back into active lead (Pb) during charging and significantly extending the cycle life.

[0070] Enhanced Conductivity: The high conductivity of graphene (electron mobility up to 15000 cm 2 / (V·s)) reduces the internal resistance of the negative electrode, improves the charge and discharge efficiency, and especially enhances the fast charging ability.

[0071] Stabilization of Electrode Structure: The porous network structure of graphene supports the active material (sponge lead), prevents the shedding of the active material during charge and discharge, and improves the mechanical strength and cycle stability.

[0072] See Figure 9 SEM images of the negative grid without graphene spraying treatment, and Figure 10 SEM images of the negative grid after graphene spraying treatment. It can be seen that the graphene coating can prevent lead sulfate (PbSO4) crystals from forming large crystals on the negative electrode surface.

[0073] Example 4: This example provides a manufacturing process for the negative electrode plate of a lead-acid battery using the present invention. The process steps are as follows: Step 1: Plate Manufacturing Manufacture the positive and negative plates. The size of the positive plate is: length 148 mm × width 132 mm × thickness 0.50 mm; grid weight: 20 g; active material weight: 165 g; single plate capacity: 10 Ah; The size of the negative plate is: length 148 mm × width 132 mm × thickness 0.30 mm; grid weight: 13 g; active material weight: 86 g; single plate capacity: 6.67 Ah.

[0074] Plate Preparation Process: Use a pasting machine to evenly coat the active material on the grid to form a wet plate. The wet plate is cured and dried in a curing and drying furnace to finally obtain a dry plate for battery assembly.

[0075] Step 2: Battery Pack Assembly Plate Combination Method: Use 2 positive plates and 3 negative plates stacked alternately to optimize the current distribution and active material utilization rate.

[0076] -Separator setting: Wrap 2 pieces of AGM separators with a thickness of 0.6 mm outside the positive plate. The size of the separator is slightly larger than the electrode to ensure effective isolation and prevent short circuit.

[0077] Tab welding: Weld and parallel-connect the tabs of 2 positive plates, and connect to the positive lead terminal; weld and parallel-connect the tabs of 3 negative plates, and connect to the negative lead terminal; Battery capacity: Since 2 pieces of 10 Ah positive plates are connected in parallel, the nominal capacity of the battery is 20 Ah.

[0078] Step 3: Battery formation and performance testing Electrolyte injection: Add an appropriate amount of dilute sulfuric acid with a density of 1.260 g / ml to the plastic container of the battery.

[0079] Formation process: Use the "three charge and two discharge" formation process for charging to optimize the activation effect of the electrode plate.

[0080] Capacity test: Test conditions: Constant current discharge at 10 A, cut-off voltage 1.75 V.

[0081] -Test results: The discharge time reaches 2 hours and 05 minutes, and the calculated capacity is 20.8 Ah, exceeding the nominal capacity of 20 Ah, indicating that the battery has good utilization rate of active materials and discharge performance.

[0082] This battery adopts an optimized electrode plate design, precise coating process and reasonable assembly method, ensuring a high energy density and stable discharge performance. The measured capacity exceeds the nominal value.

[0083] Example 5: This example provides a manufacturing process for the negative electrode plate of a lead-acid battery using the present invention. The process steps are as follows: Step 1: Electrode plate manufacturing Manufacture positive and negative electrode plates. The size of the positive electrode plate is: length 148 mm × width 132 mm × thickness 0.55 mm; grid weight: 25 g; active material weight: 160 g; single electrode plate capacity: 10 Ah; The size of the negative electrode plate is: length 148 mm × width 132 mm × thickness 0.35 mm; grid weight: 14.5 g; active material weight: 80 g; single electrode plate capacity: 6.67 Ah.

[0084] Electrode plate preparation process: Use a coating machine to evenly coat the active material on the grid to form a wet electrode plate. The wet electrode plate is cured and dried in a curing and drying furnace to finally obtain a dry electrode plate for battery assembly.

[0085] Step 2: Battery pack assembly Electrode plate combination method: Adopt an alternating stacking of 2 positive electrode plates and 3 negative electrode plates to optimize the current distribution and utilization rate of active materials.

[0086] - Separator setting: Wrap 2 pieces of AGM separators with a thickness of 0.6 mm outside the positive plate. The size of the separator is slightly larger than the electrode to ensure effective isolation and prevent short - circuit.

[0087] Tab welding: Weld and parallel - connect the tabs of 2 positive plates, and connect to the positive lead terminal; weld and parallel - connect the tabs of 3 negative plates, and connect to the negative lead terminal; Battery capacity: Since 2 pieces of 10 - Ah positive plates are connected in parallel, the nominal capacity of the battery is 20 Ah.

[0088] Step 3: Battery formation and performance testing Electrolyte injection: Add an appropriate amount of dilute sulfuric acid with a density of 1.260 g / ml into the plastic container of the battery.

[0089] Formation process: Use the "three - charge and two - discharge" formation process for charging to optimize the activation effect of the electrode plate.

[0090] Capacity testing: Testing conditions: Constant - current discharge at 10 A, cut - off voltage 1.75 V.

[0091] - Test results: The discharge time reaches 2 hours and 4 minutes, and the calculated capacity is 20.6 Ah, exceeding the nominal capacity of 20 Ah, indicating that the battery has good active - material utilization rate and discharge performance.

[0092] This battery adopts an optimized electrode - plate design, precise coating process and reasonable assembly method, ensuring high energy density and stable discharge performance. The measured capacity exceeds the nominal value.

[0093] Example 6: This example provides a manufacturing process for the negative electrode plate of a lead - acid battery using the present invention. The process steps are as follows: Step 1: Electrode - plate manufacturing Manufacture the positive electrode plate and the negative electrode plate. The size of the positive electrode plate is: length 148 mm × width 132 mm × thickness 0.60 mm; grid weight: 30 g; active - material weight: 150 g; single - plate capacity: 10 Ah; The size of the negative electrode plate is: length 148 mm × width 132 mm × thickness 0.40 mm; grid weight: 16.5 g; active - material weight: 65 g; single - plate capacity: 6.67 Ah.

[0094] Electrode - plate preparation process: Use a pasting machine to evenly coat the active material on the grid to form a wet electrode plate. The wet electrode plate is cured and dried in a curing and drying furnace, and finally a dry electrode plate is obtained for battery assembly.

[0095] Step 2: Battery - pack assembly Electrode - plate combination method: Adopt an interleaved stacking of 2 positive electrode plates and 3 negative electrode plates to optimize the current distribution and active - material utilization rate.

[0096] - Separator setting: Wrap 2 pieces of AGM separators with a thickness of 0.6 mm outside the positive electrode plate. The size of the separator is slightly larger than the electrode to ensure effective isolation and prevent short circuit.

[0097] Tab welding: Weld and connect in parallel the tabs of 2 positive electrode plates, and connect to the positive lead terminal; weld and connect in parallel the tabs of 3 negative electrode plates, and connect to the negative lead terminal; Battery capacity: Since 2 pieces of 10 Ah positive electrode plates are connected in parallel, the nominal capacity of the battery is 20 Ah.

[0098] Step 3: Battery formation and performance testing Electrolyte injection: Add an appropriate amount of dilute sulfuric acid with a density of 1.260 g / ml to the plastic container of the battery.

[0099] Formation process: Use the "three charge and two discharge" formation process for charging to optimize the activation effect of the electrode plate.

[0100] Capacity test: Test conditions: Constant current discharge at 10 A, cut-off voltage 1.75 V.

[0101] - Test results: The discharge time reaches 2 hours and 01 minute, and the calculated capacity is 20.2 Ah, exceeding the nominal capacity of 20 Ah, indicating that the battery has good active material utilization rate and discharge performance.

[0102] This battery adopts an optimized electrode plate design, precise coating process and reasonable assembly method to ensure a high energy density and stable discharge performance. The measured capacity exceeds the nominal value.

[0103] Example 7: Based on Example 1, this example provides a further optimized solution. Refer to Appendix Figure 1 Appendix Figure 5 As shown, after the battery is assembled, the positive electrode plate of the present invention forms a single-core battery. A main body 50 is provided at the end of the single-core battery. The main body 50 is a long strip structure. At least two annular cavities are provided on the main body 50. A cylindrical inner cavity penetrating the main body 50 is provided in the annular cavity. The pole column 20 can pass through the cylindrical inner cavity. An insert 51 is provided on the annular cavity. A pole column cap 51 is detachably provided on the pole column 20. The insert 51 has a round hole allowing the pole column cap 51 and the pole column 20 to pass through. Glue can be stored in the annular cavity. A groove is provided at the edge of the round hole of the insert 51. The groove is provided to facilitate unscrewing the pole column cap 51 for subsequent welding treatment of the pole column 20 and the connecting piece, and to minimize the damage to the glue sealing layer.

[0104] On both sides of the main body 50, there are buckles and a chuck 52. The chuck 52 corresponds to the buckle structure, and the two can form a clamping relationship. Adjacent single-cell batteries can form a clamped state through the chuck 52 and the buckle. A packaging bag 40 connected to a part of the main body 50 is sleeved outside the single-cell battery.

[0105] In the content of this specification, Pb is lead, PbO is lead oxide, PbO n is a higher-order oxide of lead, PbO2 is lead dioxide, and Pb(OH)2 is lead hydroxide.

[0106] It should also be noted that the orientation or positional relationship indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present application. Unless otherwise clearly specified and defined, terms such as "installed", "connected", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0107] The above-described embodiments and / or implementation manners are only used to illustrate the preferred embodiments and / or implementation manners for implementing the technology of the present invention, and do not impose any form of limitation on the implementation manners of the technology of the present invention. Any person skilled in the art, without departing from the scope of the technical means disclosed in the content of the present invention, can make some modifications or changes to other equivalent embodiments, but should still be regarded as the same technology or embodiment as the present invention in essence.

[0108] In this article, specific examples are used to elaborate on the principles and implementation manners of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application. The above is only the preferred implementation manner of the present application. It should be noted that due to the limitation of literal expression, and objectively there are infinite specific structures. For those of ordinary skill in the art, without departing from the principle of the present application, several improvements, retouches or changes can be made, or the above technical features can be combined in an appropriate manner; these improvements, retouches, changes or combinations, or directly applying the concept and technical solution of the invention to other occasions without improvement, should all be regarded as the protection scope of the present application.

Claims

1. A negative electrode plate for a lead-acid battery, characterized in that, The alloy dosage of the negative electrode plate is 1.95 - 2.47 g / Ah.

2. The negative electrode plate for a lead-acid battery according to claim 1, characterized in that, The alloy dosage of the negative plate is 0.665~0.845 g / cm 3 .

3. The negative electrode plate for lead-acid battery according to claim 1, characterized in that, The negative electrode plate includes a negative grid and negative electrode active material.

4. The negative electrode plate for lead-acid batteries according to claim 3, characterized in that, The amount of the negative electrode active material is 3.327 to 4.402 g / cm 3 .

5. The negative electrode plate for a lead-acid battery according to claim 3, characterized in that, The dosage of the negative electrode active material is 9.7 - 12.9 g / Ah.

6. The negative electrode plate for a lead-acid battery according to claim 3, characterized in that, The negative electrode active material is lead paste, and the lead paste contains a two-dimensional conductive material and glass nanotubes.

7. The negative electrode plate for a lead-acid battery according to claim 3, characterized in that, The negative grid is made of a lead plate that has been subjected to rolling treatment, pickling treatment, and then heat treatment.

8. The negative plate for a lead-acid battery according to claim 7, characterized in that, The number of rolling treatments is at least 7 times, the heat treatment temperature is 80°C - 90°C, and the heat treatment time is 12 h - 24 h.

9. The negative electrode plate for a lead-acid battery according to claim 7, characterized in that, The surface of the negative grid is subjected to spraying treatment after pickling treatment.

10. A single cell, characterized in that, The single cell has a negative electrode plate, a positive electrode plate, and a separator for a lead-acid battery as described in any one of claims 1 - 9.

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