Lead-acid battery with hybrid anode structure

Abstract

The utility model provides a lead-acid battery with a mixed anode structure, which belongs to the technical field of battery production, and includes a plurality of positive plates and a plurality of negative plates, wherein the positive plates and the negative plates are arranged alternately; the plurality of positive plates are composed of a plurality of cast positive plates and a plurality of mesh positive plates; the thickness of the cast positive plates is greater than the thickness of the mesh positive plates, and the ratio of the number of cast positive plates to the number of mesh positive plates is ≥1.5. The lead-acid battery with a mixed anode structure provided by the utility model utilizes the principle that the mesh positive plate is thinner than the cast positive plate and has poorer durability under the same state, and slows down the corrosion rate of the cast positive plate by adopting the combination of the cast positive plate and the mesh positive plate, thereby improving the overall corrosion resistance of the anode structure, thereby improving the cycle durability of the battery, and extending the service life of the battery; and at the same time reducing the production cost.

Description

Technical Field

[0001] The utility model belongs to the technical field of battery production, and more specifically relates to a lead-acid battery with a mixed anode structure. Background Art

[0002] A battery is a device that converts chemical energy and direct current energy into each other and can be restored and reused by charging after discharge. A lead-acid battery consists of a positive plate, a negative plate and an electrolyte. The positive and negative plates consist of plates and active substances. The plates are lead-based alloys, 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 flooded starter lead-acid battery is in a state of long-term floating charge. While the lead sulfate on the positive plate is converted into lead dioxide, the lead and other metals in the positive plate alloy are also oxidized by the high oxidation potential of the positive electrode. That is, when the battery is in an open circuit state, the positive plate lead alloy and lead dioxide form a micro-battery in the sulfuric acid electrolyte. Self-discharge oxidizes the lead alloy and reduces lead dioxide to lead sulfate. The final result of positive plate corrosion is positive plate rot and battery failure.

[0004] Currently, cast grids or stretched grids are mostly used for positive electrode grids. Cast grids have a stable structure and good corrosion resistance, but cast grids are heavy and expensive. Stretched grids are light and low in cost, but they are thinner and have poor corrosion resistance. Utility Model Content

[0005] The utility model aims to provide a lead-acid storage battery with a mixed anode structure, aiming to slow down the corrosion speed of the positive plate and reduce the production cost of the storage battery.

[0006] To achieve the above-mentioned purpose, the technical solution adopted by the utility model is: to provide a lead-acid battery with a mixed anode structure, including: a plurality of positive plates and a plurality of negative plates, the positive plates and the negative plates are arranged alternately; the plurality of positive plates are composed of a plurality of cast positive plates and a plurality of drawn mesh positive plates; the thickness of the cast positive plates is greater than the thickness of the drawn mesh positive plates, and the ratio of the number of the cast positive plates to the number of the drawn mesh positive plates is ≥1.5.

[0007] As another embodiment of the present application, the cast positive electrode plates and the drawn positive electrode plates are arranged alternately.

[0008] As another embodiment of the present application, the difference between the thickness of the cast positive electrode plate and the thickness of the drawn positive electrode plate is ≤0.7 mm.

[0009] As another embodiment of the present application, the thickness of the cast positive electrode plate is 1.4 mm-1.7 mm, and the thickness of the drawn positive electrode plate is 0.9 mm-1.2 mm.

[0010] As another embodiment of the present application, the negative electrode plate is a stretched mesh negative electrode plate, and the number of the negative electrode plates is consistent with the sum of the number of the cast positive electrode plates and the stretched mesh positive electrode plates.

[0011] As another embodiment of the present application, the cast positive electrode plate includes a plate body and an outer wrapping layer, and the outer wrapping layer is a mesh structure or a strip-shaped protrusion structure.

[0012] As another embodiment of the present application, the thickness of the outer wrapping layer is less than one fifth of the thickness of the cast positive electrode plate.

[0013] As another embodiment of the present application, the junction between the transverse ribs and the longitudinal ribs of the cast positive electrode plate is a conical transition structure.

[0014] The beneficial effect of the lead-acid battery with a hybrid anode structure provided by the utility model is that: compared with the prior art, the lead-acid battery with a hybrid anode structure of the utility model sets the anode structure of the battery as a hybrid anode structure formed by a combination of two positive plates, and utilizes the principle that the drawn positive plate is thinner than the cast positive plate and has poorer durability under the same state, and by adopting a combination of the cast positive plate and the drawn positive plate, the corrosion rate of the cast positive plate is slowed down, the overall corrosion resistance of the anode structure is improved, and the cycle durability of the battery is improved, and the service life of the battery is extended; at the same time, the production cost is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 A schematic diagram of the structure of a lead-acid battery with a mixed anode structure provided in an embodiment of the utility model;

[0017] Figure 2 A schematic structural diagram of a conical transition structure provided in an embodiment of the utility model.

[0018] In the figure: 1. Cast positive electrode plate; 2. Mesh positive electrode plate; 3. Negative electrode plate; 4. Separator; 5. Transverse ribs; 6. Longitudinal ribs; 7. Conical transition structure. DETAILED DESCRIPTION

[0019] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0020] See also Figure 1 , the lead-acid battery with a mixed anode structure provided by the utility model is now described. The lead-acid battery with a mixed anode structure includes a plurality of positive plates and a plurality of negative plates 3, and the positive plates and the negative plates 3 are arranged alternately; the plurality of positive plates are composed of a plurality of cast positive plates 1 and a plurality of mesh positive plates 2; the thickness of the cast positive plates 1 is greater than the thickness of the mesh positive plates 2, and the ratio of the number of cast positive plates 1 to the number of mesh positive plates 2 is ≥1.5.

[0021] Compared with the prior art, the lead-acid battery with a mixed anode structure provided by the utility model sets the anode structure of the battery as a mixed anode structure formed by combining two positive plates. The utility model utilizes the principle that the drawn mesh positive plate 2 is thinner than the cast positive plate 1 and has poorer durability under the same state. By adopting the combination of the cast positive plate 1 and the drawn mesh positive plate 2, the corrosion rate of the cast positive plate 1 is slowed down, the overall corrosion resistance of the anode structure is improved, and the cycle durability of the battery is improved, thereby extending the service life of the battery; at the same time, the production cost is reduced.

[0022] The stretched positive electrode plate 2 can be replaced by a punched positive electrode plate.

[0023] During the comparative test, the lead-acid batteries made of different positive plates were subjected to cycle endurance IV75℃ performance test. The cycle endurance IV performance test of ordinary positive cast batteries reached 2640 times; the cycle endurance IV performance test of ordinary full-drawn / punched batteries reached 1680 times.

[0024] Furthermore, in order to improve the protective effect of the positive plate, the cast positive plate 1 and the drawn positive plate 2 are both made of lead-calcium-tin alloy material, the cast positive plate 1 has a calcium content of 0.05%-0.10% and a tin content of 0.6%-0.8%; the drawn positive plate 2 has a calcium content of 0.05%-0.10% and a tin content of 1.2%-2.0%; the conductivity of the drawn positive plate 2 is improved by changing the tin content. The impedance values ​​of the above two positive plates were tested using an electrochemical workstation, and the impedance values ​​of the two were measured after polarization for 4 hours at 1.3V, 0.9V, -0.3V, and -0.5V, respectively, as shown in Table 1.

[0025] Table 1 Impedance values ​​at various potentials

[0026]

[0027] According to the experiment, 1.3V is the potential for PbO2 generation, and 0.9V is the electrochemical potential for the PbO2→PbSO4 reaction. The conductivity of the stretched positive plate 2 is improved after the Sn content is increased, that is, the conductivity of the stretched positive plate 2 is much higher than that of the cast positive plate 1. Inside the battery cell, the positive plates are connected in parallel. When the battery is charged at a constant voltage, the stretched positive plate 2 with good conductivity will bear a larger current, which can protect the cast positive plate 1 connected in parallel, slow down the corrosion of the cast positive plate 1, and thus increase the service life of the battery.

[0028] In order to improve the protection efficiency, the cast positive plate 1 and the mesh positive plate 2 are arranged alternately, forming a distribution state of negative plate 3-cast positive plate 1-negative plate 3-mesh positive plate 2-negative plate 3-cast positive plate 1, or a distribution state of negative plate 3-mesh positive plate 2-negative plate 3-cast positive plate 1-negative plate 3-mesh positive plate 2. By alternately installing the cast positive plate 1 and the mesh positive plate 2, the mesh positive plate 2 that is easily corroded is evenly distributed in the battery cell to ensure the stable working state of the battery.

[0029] The cycle durability of the cast positive plate 1 is higher than that of the drawn positive plate 2, so the ratio of the number of cast positive plates 1 to the number of drawn positive plates 2 is set to ≥1.5; the proportion of the cast positive plate 1 is ensured, thereby ensuring the cycle durability of the positive plate and improving the service life of the battery.

[0030] Taking the example of setting five positive plates in each battery cell, the five positive plates are 3 cast positive plates 1 and 2 mesh positive plates 2. The mesh positive plate 2 is thin, light and low in cost. The appropriate use of the mesh positive plate 2 can reduce the production cost; and the mesh positive plate 2 is combined with the cast positive plate 1 to protect the cast positive plate 1 by sacrificing the mesh positive plate 2, which can achieve corrosion protection of the cast positive plate, thereby ensuring the cycle durability of the battery. Taking the five positive plates including three cast positive plates 1 and two mesh positive plates 2 as an example, the battery made from them is subjected to cycle durability IV75℃ performance test of lead-acid battery. The cycle durability IV performance test of the battery reaches 2638 times, and its cycle durability performance is relatively the same as that of the battery using only cast positive plates 1. However, since nearly one third of the cast positive plates 1 in the battery are replaced with the drawn mesh positive plates 2, the production cost is reduced to a great extent while the service life of the battery is ensured.

[0031] Specifically, in order to meet the manufacturing process requirements of the positive electrode plate, the thickness of the cast positive electrode plate 1 is greater than the thickness of the stretched positive electrode plate 2; the difference between the thickness of the cast positive electrode plate 1 and the thickness of the stretched positive electrode plate 2 is ≤0.7mm. Specifically, the thickness of the cast positive electrode plate 1 is 1.4mm-1.7mm, and the thickness of the stretched positive electrode plate 2 is 0.9mm-1.2mm.

[0032] Since the corrosion rate of the negative electrode plate 3 is lower than that of the positive electrode plate, the negative electrode plate 3 can be a stretched mesh negative electrode plate 3; the number of the negative electrode plates 3 is consistent with the total number of the positive electrode plates, that is, the number of the negative electrode plates 3 is consistent with the total number of the cast positive electrode plates 1 and the stretched mesh positive electrode plates 2.

[0033] The negative electrode plate 3 is coated with a PE separator 4, and each cell of the battery tank is loaded with 5 positive plates and 5 negative plates 3, and at least 3 of the 5 positive plates are cast positive plates 1; and the positive plates and negative plates 3 are arranged alternately and connected together by cast welding to form a pole group structure. During the cast welding process, the mold temperature of the cast welding positive plate is 460℃-500℃, preferably 470℃±5℃. The mold temperature of the cast welding negative plate 3 is 410℃-440℃, preferably 420℃±5℃.

[0034] In some possible embodiments, the cast positive electrode plate 1 includes a plate body and an outer wrapping layer, and the outer wrapping layer is a mesh structure or a strip-shaped protrusion structure.

[0035] An outer wrapping layer is provided on the outer side of the grid structure of the cast positive plate 1 , and the outer wrapping layer can be constructed by casting and other processes. The outer wrapping layer is consistent with the material of the stretched mesh positive plate 2 , and its conductive performance is greater than the conductor performance of the cast positive plate 1 .

[0036] The outer wrapping layer is a mesh structure or a strip-shaped protruding structure wrapped around the outside of the cast positive plate 1. In the initial state of the battery, the impedance value of the outer wrapping layer of the cast positive plate 1 is consistent with that of the mesh positive plate 2, ensuring the stability of charging and discharging; and the outer wrapping layer is located on the outside of the cast positive plate 1, and its impedance value is less than the impedance value of the plate body of the cast positive plate 1, so the outer wrapping layer will corrode first. The corrosion process of the outer wrapping layer can further protect the plate body.

[0037] Optionally, the thickness of the outer wrapping layer is less than one fifth of the thickness of the cast positive electrode plate 1 .

[0038] like Figure 2 As shown, in order to reduce the corrosion rate and protect the connection between the transverse ribs 5 and the longitudinal ribs 6, the connection between the transverse ribs 5 and the longitudinal ribs 6 of the cast positive plate 1 is set as a conical transition structure 7. The cross-sections of the transverse ribs 5 and the longitudinal ribs 6 are circular, and the corresponding conical transition structure 7 is coaxially arranged with the transverse ribs 5 / longitudinal ribs 6.

[0039] The conical transition structure 7 is a conical structure wrapped around the transverse ribs 5 and the longitudinal ribs 6. It extends from the intersection of the transverse ribs 5 and the longitudinal ribs 6 along the length direction of the transverse ribs 5 or the longitudinal ribs 6, and its outer diameter gradually decreases along the extension direction.

[0040] Optionally, the lengths of the multiple conical transition structures 7 located at the same intersection are consistent.

[0041] The connection between the multiple conical transition structures 7 located at the same intersection is an arc-shaped transition to facilitate casting.

[0042] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A lead-acid battery with a mixed anode structure, characterized in that: The invention comprises a plurality of positive plates and a plurality of negative plates (3), wherein the positive plates and the negative plates (3) are arranged alternately; the plurality of positive plates are composed of a plurality of cast positive plates (1) and a plurality of drawn positive plates (2); the thickness of the cast positive plates (1) is greater than the thickness of the drawn positive plates (2), and the ratio of the number of the cast positive plates (1) to the number of the drawn positive plates (2) is ≥1.

5.

2. The lead-acid battery with a mixed anode structure as claimed in claim 1, characterized in that: The cast positive electrode plates (1) and the stretched positive electrode plates (2) are arranged alternately.

3. The lead-acid battery with a mixed anode structure as claimed in claim 1, characterized in that: The difference between the thickness of the cast positive electrode plate (1) and the thickness of the stretched positive electrode plate (2) is ≤0.7 mm.

4. The lead-acid battery with a mixed anode structure as claimed in claim 3, characterized in that: The thickness of the cast positive electrode plate (1) is 1.4 mm to 1.7 mm, and the thickness of the stretched positive electrode plate (2) is 0.9 mm to 1.2 mm.

5. The lead-acid battery with a mixed anode structure as claimed in claim 1, characterized in that: The negative electrode plates (3) are stretched mesh negative electrode plates (3), and the number of the negative electrode plates (3) is consistent with the number of the cast positive electrode plates (1) and the stretched mesh positive electrode plates (2).

6. The lead-acid battery with a mixed anode structure as claimed in claim 1, characterized in that: The cast positive electrode plate (1) comprises an electrode plate body and an outer wrapping layer, wherein the outer wrapping layer is a mesh structure or a strip-shaped protrusion structure.

7. The lead-acid battery with a mixed anode structure as claimed in claim 6, characterized in that: The thickness of the outer wrapping layer is less than one fifth of the thickness of the cast positive electrode plate (1).

8. The lead-acid battery with a mixed anode structure as claimed in claim 6, characterized in that: The junction between the transverse ribs (5) and the longitudinal ribs (6) of the cast positive electrode plate (1) is a conical transition structure (7).

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