Lead-acid battery with a hybrid anode structure

Abstract

Lead-acid battery with a hybrid anode structure, characterized in that it comprises a plurality of positive electrode plates and a plurality of negative electrode plates (3), wherein the positive electrode plates and the negative electrode plates (3) are arranged alternately, wherein the plurality of positive electrode plates comprises a plurality of cast positive electrode plates (1) and a plurality of mesh-stretched positive electrode plates (2), wherein the thickness of the cast positive electrode plates (1) is greater than the thickness of the mesh-stretched positive electrode plates (2), and wherein the ratio of the number of cast positive electrode plates (1) to the number of mesh-stretched positive electrode plates (2) is ≥1.5.

Description

TECHNICAL FIELD

[0001] The present utility model relates to the technical field of battery production, in particular a lead-acid battery with a hybrid anode structure. STATE OF THE ART

[0002] A battery is a device that converts chemical energy and direct current energy into each other. It can be reused after discharge and restored by recharging. A lead-acid battery consists of a positive electrode plate, a negative electrode plate, and an electrolyte. The positive and negative electrode plates consist of the electrode plate and the active substance. The electrode plate is a lead-based alloy, the positive active substance is lead dioxide (PbO2), the negative active substance is spongy metallic lead (Pb), and the electrolyte is dilute sulfuric acid.

[0003] When the car is running, the liquid-rich starter lead-acid battery is in a state of long-term maintenance charge. The lead sulfate of the positive electrode plate is simultaneously converted into lead dioxide. The lead alloy of the positive electrode plate and other metals are also oxidized by the high oxidation potential of the positive electrode. In other words, the battery is in an open circuit, the lead alloy of the electrode plate and the lead dioxide in the sulfuric acid electrolyte form a microcell. Self-discharge leads to the oxidation of the lead alloy, and the lead dioxide is reduced to lead sulfate. The ultimate result of corrosion of the positive electrode plate is the deterioration of the positive electrode plate and the failure of the battery.

[0004] Currently, positive plate gratings are mostly made of cast plate gratings or mesh-stretched plate gratings. The structure of cast plate gratings is stable and corrosion resistance is better, but the weight of cast plate gratings is heavy and the cost is high; the mesh-stretched plate gratings are light and low in weight, but the thickness of the mesh-stretched plate gratings is thin and the corrosion resistance is poor. CONTENTS OF THE PRESENT UTILITY MODEL

[0005] The purpose of the present utility model is to provide a lead-acid battery with a hybrid anode structure that aims to slow down the corrosion rate of the positive electrode plate while reducing the production cost of the battery.

[0006] To achieve the above-mentioned purpose, the utility model applies the following technical solution: The present utility model provides a lead-acid battery having a hybrid anode structure comprising a plurality of positive electrode plates and a plurality of negative electrode plates, wherein the positive electrode plates and the negative electrode plates are arranged alternately, wherein the plurality of positive electrode plates comprises a plurality of cast positive electrode plates and a plurality of mesh-stretched positive electrode plates, wherein the thickness of the cast positive electrode plates is greater than the thickness of the stretched positive electrode plates, and wherein the ratio of the number of cast positive electrode plates to the number of mesh-stretched positive electrode plates is ≥ 1.5.

[0007] As another embodiment of the present application, the cast positive electrode plates (1) and the mesh-stretched positive electrode plates (2) are alternately arranged in rows.

[0008] As another embodiment of the present application, the difference between the thickness of the cast positive electrode plates (1) and the thickness of the mesh-stretched positive electrode plates (2) is ≤ 0.7 mm.

[0009] As another embodiment of the present application, the thickness of the cast positive electrode plates (1) is 1.4 mm-1.7 mm and the thickness of the mesh-stretched positive electrode plates (2) is 0.9 mm-1.2 mm.

[0010] As another embodiment of the present application, the negative electrode plate (3) is a mesh-stretched negative electrode plate (3), the number of the negative electrode plates (3) is equal to the sum of the number of the cast positive electrode plates (1) and the mesh-stretched positive electrode plates (2).

[0011] As another embodiment of the present application, the molded positive electrode plate (1) comprises a plate body and an outer cladding layer, wherein the outer cladding layer is a mesh structure or a strip-shaped raised structure.

[0012] As another embodiment of the present application, the thickness of the outer cladding layer is less than one-fifth of the thickness of the molded positive electrode plate (1).

[0013] As another embodiment of the present application, the connection point between transverse bars (5) and longitudinal bars (6) of the cast positive electrode plate (1) is a conical transition structure (7).

[0014] The lead-acid battery with a hybrid anode structure of the present utility model has the following advantage: Compared with the prior art, the lead-acid battery with a hybrid anode structure of the present utility model has a hybrid anode structure formed by combining two positive electrode plates. The present utility model is based on the principle that the mesh-stretched positive electrode plate is thinner than the cast positive electrode plate and has inferior durability under the same condition.The use of the cast positive electrode plate and the mesh-knitted positive electrode plate slows down the corrosion rate of the cast positive electrode plate and improves the overall corrosion resistance of the anode structure, thereby improving the cyclic durability of the battery and extending the battery life; at the same time, the production cost is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the attached drawings used in the description of the embodiments are briefly described below. Of course, the attached drawings in the following description are only some of the embodiments of the present utility model, and those skilled in the art can create other attached drawings based on these drawings without any creative effort. Fig. 1 shows a schematic structural diagram of a lead-acid battery with a hybrid anode structure in an embodiment of the present utility model; Fig. 2 shows a schematic structural representation of a conical transition structure in an embodiment of the present utility model.

[0016] Reference list: 1. cast positive electrode plate; 2. mesh-stretched positive electrode plate; 3. negative electrode plate; 4. separator plate; 5. transverse bar; 6, longitudinal bar; 7. conical transition structure. DETAILED DESCRIPTION

[0017] In order to make the technical problems, technical solutions, and advantageous effects to be solved by the present utility model clearer and more understandable, the present utility model is described in more detail below in conjunction with the attached drawings and embodiments. It should be understood that the specific embodiments described herein serve only to illustrate the present utility model and are not intended to limit the present utility model.

[0018] As in the Fig.1, a lead-acid battery with a hybrid anode structure is described, which is provided by the present utility model. The lead-acid battery with a hybrid anode structure comprises a plurality of positive electrode plates and a plurality of negative electrode plates (3), wherein the positive electrode plates and the negative electrode plates (3) are arranged alternately, wherein the plurality of positive electrode plates comprises a plurality of cast positive electrode plates (1) and a plurality of mesh-stretched positive electrode plates (2), wherein the thickness of the cast positive electrode plates (1) is greater than the thickness of the stretched positive electrode plates (2), and wherein the ratio of the number of cast positive electrode plates (1) to the number of mesh-stretched positive electrode plates (2) is ≥1.5.

[0019] Compared with the prior art, in the lead-acid battery with a hybrid anode structure of the present utility model, the anode structure of the battery is a hybrid anode structure formed by combining two positive electrode plates. The present utility model is based on the principle that the mesh-stretched positive electrode plate 2 is thinner than the cast positive electrode plate 1 and has inferior durability under the same condition. By using the cast positive electrode plate 1 and the mesh-knitted positive electrode plate 2, the corrosion rate of the cast positive electrode plate 1 is slowed and the overall corrosion resistance of the anode structure is improved, thereby improving the cyclic durability of the battery and extending the battery life; at the same time, production costs are reduced.

[0020] The mesh-stretched positive electrode plate 2 can be replaced by a perforated positive electrode plate.

[0021] During the comparison test, lead-acid batteries with different positive electrode plates were tested for their IV cycle life at 75°C. The IV cycle life performance test of the standard cast positive electrode battery reached 2640 cycles; the IV cycle life performance test of an ordinary fully drawn / punched battery reached 1680 cycles.

[0022] To improve the protective effect of the positive electrode plate, the cast positive electrode plate 1 and the mesh-stretched positive electrode plate 2 are made of lead-calcium-tin alloy. The material of the cast positive electrode plate 1 has a calcium content of 0.05%-0.10% and a tin content of 0.6%-0.8%; the material of the mesh-stretched positive electrode plate 2 has a calcium content of 0.05%-0.10% and a tin content of 1.2%-2.0%; the electrical conductivity of the mesh-stretched positive electrode plate 2 is improved by changing the tin content. The impedance values ​​of the above-mentioned two positive electrode plates were tested using an electrochemical workstation, and the impedance values ​​of the two electrode plates were measured after 4 hours of polarization at 1.3V, 0.9V, -0.3V, and -0.5V, respectively, as shown in Table 1. Table 1 Impedance values ​​at different potentials Potential / Impedance 1.3V 0.9V -0.3V -0.5V R ct (cast plate grid) / Ω 653 12551 20164 69315 R ct (networked / perforated) / Ω 98.54 3715 4880 19731

[0023] According to experiments, 1.3V is the generation potential of PbO2, and 0.9V is the electrochemical reaction potential of PbO2→PbSO4. Increasing the Sn content in the mesh-stretched positive electrode plate 2 improves the electrical conductivity, that is, the electrical conductivity of the mesh-stretched positive electrode plate 2 is much higher than that of the cast positive electrode plate 1. When the battery is charged at a constant voltage, the conductivity of the mesh-stretched positive electrode plate 2 can bear a larger current. It can be connected in parallel with the cast positive electrode plate 1 to play a protective role, slowing down the corrosion of the cast positive electrode plate 1, and thus prolonging the battery life.

[0024] In order to improve the protective effect, the cast positive electrode plate 1 and the mesh-stretched positive electrode plate 2 are arranged in alternate rows and form a distribution state of the negative electrode plate 3 - the cast positive electrode plate 1 - the negative electrode plate 3 - the mesh-stretched positive electrode plate 2 - the negative electrode plate 3 - the cast positive electrode plate 1, or a distribution state of the negative electrode plate 3 - the mesh-stretched positive electrode plate 2 - the negative electrode plate 3 - the cast positive electrode plate 1 - the negative electrode plate 3 - the mesh-stretched positive electrode plate 2.By alternately installing the cast positive electrode plate 1 and the mesh-stretched positive electrode plate 2, the corrosion-prone mesh-stretched positive electrode plate 2 is evenly distributed in a single cell of the battery to ensure a stable operating state of the battery.

[0025] The cycle life of the cast positive electrode plate 1 is higher than that of the mesh-stretched positive electrode plate 2, so the ratio between the number of cast positive electrode plates 1 and the number of mesh-stretched positive electrode plates 2 is set to ≥1.5 to ensure the proportion of the cast positive electrode plate 1, which in turn ensures the cycle life of the positive electrode plate and improves the battery life.

[0026] For example, if five positive electrode plates are used in each battery cell, three cast positive electrode plates 1 and two mesh-stretched positive electrode plates 2 are used for the five positive electrode plates. The mesh-stretched positive electrode plates 2 are thinner, lighter, and lower in cost, so the production cost can be reduced accordingly by using the mesh-stretched positive electrode plates 2; and the use of the mesh-stretched positive electrode plate 2 and the cast positive electrode plate 1 in combination with the mesh-stretched positive electrode plate 2 to protect the cast positive electrode plate 1 enables corrosion protection of the cast positive electrode plate, ensuring the cycle stability of the battery.With five positive electrode plates, including three cast positive electrode plates 1 and two mesh-stretched positive electrode plates 2, as an example, the battery from the lead-acid battery for the cycle life IV 75 °C performance test, the battery cycle life IV performance test reaches 2638 times, its cycle life is relatively flat compared with the battery with cast positive electrode plates 1. However, by replacing nearly one-third of the cast positive electrode plates 1 in the battery with the positive mesh-stretched positive electrode plates 2, the cycle life of the battery is ensured while the production cost is reduced to a greater extent.

[0027] In order to meet the requirements of the production process of the positive electrode plate, the thickness of the cast positive electrode plate 1 is greater than the thickness of the mesh-stretched positive electrode plate 2. The difference between the thickness of the cast positive electrode plate 1 and the thickness of the mesh-stretched positive electrode plate 2 is ≤0.7mm, that is, the thickness of the cast positive electrode plate 1 is 1.4mm-1.7mm and the thickness of the mesh-stretched positive electrode plate 2 is 0.9mm-1.2mm.

[0028] Since the corrosion rate of the negative electrode plate 3 is lower than the corrosion rate of the positive electrode plate, the negative electrode plate 3 can be used as a mesh-stretched negative electrode plate 3. The number of negative electrode plates 3 corresponds to the total number of positive electrode plates, that is, the number of negative electrode plates 3 corresponds to the sum of the cast positive electrode plate 1 and the mesh-stretched positive electrode plate 2.

[0029] The negative electrode plate 3 is wrapped with a PE separator plate 4, and the battery tank is equipped with five positive electrode plates and five negative electrode plates 3 per single chamber. At least three cast positive electrode plates 1 are among the five positive electrode plates. The positive electrode plates and the negative electrode plates 3 are alternately arranged and joined by cast welding to form a pole group structure. During the casting and welding process, the temperature of the mold for casting and welding the positive electrode plate is 460°C-500°C, preferably 470°C±5°C. The temperature of the mold for casting and welding the negative electrode plate 3 is 410°C-440°C, preferably 420°C±5°C.

[0030] In some possible embodiments, the cast positive electron plate 1 comprises a plate body and an outer cladding layer, wherein the outer cladding layer is a mesh structure or a strip-shaped raised structure.

[0031] The outer cladding layer is located on the outside of the plate lattice structure of the cast positive electron plate 1. The outer cladding layer can be manufactured by a method such as casting, and the outer cladding layer is consistent with the material of the mesh-stretched positive electron plate 2, and its electrical conductivity is greater than that of the conductive properties of the cast positive electron plate 1.

[0032] The outer cladding layer is a mesh structure or a strip-shaped raised structure wrapped around the outside of the cast positive electron plate 1. In the initial state of the battery, the impedance values ​​of the outer cladding layer of the cast positive electron plate 1 and the mesh-stretched positive electron plate 2 are the same, ensuring the stability of charging and discharging. The outer cladding layer is located on the outside of the cast positive electron plate 1, and its impedance value is smaller than the impedance value of the plate body of the cast positive electron plate 1, and the outer cladding layer is corroded first. The corrosion process of the outer cladding layer can also ensure the protection of the plate body.

[0033] Optionally, the thickness of the outer cladding layer is less than one-fifth of the thickness of the cast positive electrode plate 1.

[0034] As in Fig. As shown in Figure 2, the junction between the transverse bars 5 and the longitudinal bars 6 of the cast positive electrode plate 1 is provided with a conical transition structure 7 to reduce the corrosion rate and protect the junction between the transverse bars 5 and the longitudinal bars 6. The transverse bars 5 and the longitudinal bars 6 have a circular cross-section, and the corresponding conical transition structure 7 is arranged coaxially with the transverse bars 5 / longitudinal bars 6.

[0035] The conical transition structure 7 is a conical structure wrapped around the transverse bar 5 and the longitudinal bar 6 and extending from the intersection point of the transverse bar 5 and the longitudinal bar 6 along the longitudinal direction of the transverse bar 5 or the longitudinal bar 6, with the outer diameter gradually decreasing in the direction of its extension.

[0036] Optionally, the multiple conical transition structures 7 located at the same intersection point have the same length.

[0037] The connection of the several conical transition structures 7 located at the same intersection point is a curved transition to facilitate casting.

[0038] The foregoing is merely an improved embodiment of the present utility model and is not intended to limit the present utility model. All modifications, equivalent substitutions, and improvements made within the spirit and principles of the utility model fall within the scope of protection of the present utility model.

Claims

[1] Lead-acid battery with a hybrid anode structure, characterized by in that it comprises a plurality of positive electrode plates and a plurality of negative electrode plates (3), wherein the positive electrode plates and the negative electrode plates (3) are arranged alternately, wherein the plurality of positive electrode plates comprises a plurality of cast positive electrode plates (1) and a plurality of mesh-stretched positive electrode plates (2), wherein the thickness of the cast positive electrode plates (1) is greater than the thickness of the stretched positive electrode plates (2), and wherein the ratio of the number of cast positive electrode plates (1) to the number of mesh-stretched positive electrode plates (2) is ≥1.

5. [2] A lead-acid battery having a hybrid anode structure according to claim 1, characterized bythat the cast positive electrode plates (1) and the mesh-stretched positive electrode plates (2) are arranged alternately in rows. [3] A lead-acid battery having a hybrid anode structure according to claim 1, characterized by that the difference between the thickness of the cast positive electrode plates (1) and the thickness of the mesh-stretched positive electrode plates (2) is ≤ 0.7 mm. [4] Lead-acid battery with a hybrid anode structure according to claim 3, characterized by that the thickness of the cast positive electrode plates (1) is 1.4 mm-1.7 mm and the thickness of the mesh-stretched positive electrode plates (2) is 0.9 mm-1.2 mm. [5] Lead-acid battery with a hybrid anode structure according to claim 1, characterized bythat the negative electrode plate (3) is a net-stretched negative electrode plate (3), wherein the number of negative electrode plates (3) is equal to the sum of the number of cast positive electrode plates (1) and net-stretched positive electrode plates (2). [6] A lead-acid battery having a hybrid anode structure according to claim 1, characterized by that the cast positive electrode plate (1) comprises a plate body and an outer cladding layer, wherein the outer cladding layer is a mesh structure or a strip-shaped raised structure. [7] Lead-acid battery with a hybrid anode structure according to claim 6, characterized by that the thickness of the outer cladding layer is less than one fifth of the thickness of the cast positive electrode plate (1). [8] Lead-acid battery with a hybrid anode structure according to claim 6, characterized bythat the connection point between transverse bars (5) and longitudinal bars (6) of the cast positive electrode plate (1) is a conical transition structure (7).

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