A horizontal lead-acid battery with a filler and an assembly method thereof

Abstract

The present invention provides a horizontal lead-acid battery with fillers and an assembly method thereof, including a battery case and a battery electrode group composed of positive and negative plates and separators. It is characterized in that fillers which are injected in a liquid form at room temperature and converted into a solid state after curing treatment are arranged around the positive and negative plates. These fillers can fill all the plate gaps, tightly wrap the plates, limit the expansion of the plates, and enable the plates to expand only in the direction perpendicular to the plate plane, avoiding short circuits between the positive and negative plates. Moreover, the extremely high assembly pressure of the horizontal battery restricts the expansion of the active material, ensures the integrity of the active material, and greatly improves the service life of the horizontal lead-acid battery.

Description

Technical Field

[0001] The present invention relates to a storage battery, and more particularly to a horizontal lead-acid battery with fillers for preventing short circuit between positive and negative plates and an assembling method thereof.

Background Art

[0002] The lead-acid battery originated from the research of Gaston Plante in 1859 on the charge and discharge of Pb electrodes in a 10wt% sulfuric acid solution. In 1881, Camille Faure coated a lead paste composed of red lead, sulfuric acid and water on a lead plate as an electrode, and Ernest Volckmar changed the lead plate to a lead plate grid. These two technologies alleviated the softening and shedding of the positive and negative lead pastes of the lead-acid battery and effectively improved the capacity of the lead-acid battery. The structure of the lead-acid battery was thus basically formed and became mature. After more than 150 years of research and improvement, the lead-acid battery has been innovated in the directions of electrode plates, additives, separator materials and manufacturing processes. At present, the production and storage capacity of lead-acid batteries still rank first among chemical power sources and are making great contributions to the development and progress of human society. Because of its advantages such as stable and reliable performance, no memory effect, low price, and the ability to make single-cell large-capacity batteries, lead-acid batteries have been widely used as automotive starting power sources, uninterruptible power supplies, power sources and energy storage power supplies from electric bicycles to diesel submarines, etc.

[0003] The basic structure of a traditional lead-acid battery is that positive and negative plates are formed by grids coated with lead paste. The positive and negative plates are separated by a diaphragm. After the positive and negative plates are welded to the corresponding bus bars, the battery current is connected to the outside through the pole columns. The battery cover seals the battery to prevent the electrolyte from flowing out. The electrode plates of traditional lead-acid batteries are placed vertically, and during use, a phenomenon of electrolyte stratification occurs, that is, the polarization phenomenon of electrolyte concentration difference, which is one of the main reasons for the decrease in battery capacity and the shortening of battery life.

[0004] To solve the above problems, a horizontal lead-acid battery has been developed: the electrode plate is a quasi-bipolar structure, that is, on one side of the grid, a positive active material is coated as the positive electrode plate, and on the other side, a negative active material is coated as the negative electrode plate; the bipolar plates are separated by a diaphragm and stacked horizontally and staggered at a certain position, and then a pressure frame is installed and fixed to form a battery module, which is installed in a battery tank, sealed after cast welding, and then acid-filled and formed to finally make a horizontal battery. Although this horizontal lead-acid battery solves the problem of electrolyte stratification, has a small internal resistance and is lightweight, the series connection between cells is directly realized by lead wires connecting the bipolar plates without welding (for traditional cell series connection, first the welded positive electrode lead-out end of the previous unit and the welded negative electrode lead-out end of the next unit are welded together to form a series connection of adjacent cells).

[0005] However, for lead-acid batteries, during the process of electrochemical reactions, the positive and negative active materials will experience varying degrees of volume expansion, piercing the separator, coming into contact with the positive active material and causing a short circuit, or causing a short circuit by contacting the positive and negative plates through the gaps at the edges of the plates, resulting in battery failure. Therefore, preventing the expansion of the battery active material from causing contact short circuits between the positive and negative plates is an effective means to extend the service life of horizontal lead-acid batteries.

[0006] Using microcrystalline wax as a filler and filling it around the positive and negative plates can, to a certain extent, achieve the purpose of avoiding short circuits. However, this microcrystalline wax needs to be melted by heating to 90 - 120 °C and then quickly injected (this microcrystalline wax can only remain in a liquid state above 90 °C). At this time, not only will the electrolyte evaporate, but also due to the relatively low overall temperature of the battery, if the wax filling channel is blocked, the wax at the blocked part will quickly solidify, extremely likely causing one side of the gap between the plates within the same battery electrode group to be filled with wax while the other side cannot be fully filled. The consequences are as follows: on the unfilled side, the plates will expand more rapidly during charge and discharge cycles, and contact short circuits will occur even earlier. Therefore, the actual application effect of this solution is very poor.

[0007] Patent application CN2018216856114 discloses a horizontal lead-acid battery for preventing expansion short circuits of plates. By providing a receiving groove on the battery case to receive the expanded negative active material, the occurrence of short circuits between the positive and negative electrodes is reduced. When the manufacturing and assembly accuracy of the plates is high enough, the expanded part of the plate just extends into the receiving groove, which can delay the contact short circuit between the positive and negative plates. However, because the space of the receiving groove is limited, after the receiving groove is filled, the active material will overflow from the receiving groove, and the positive and negative plates will still contact and cause a short circuit, which cannot be completely eliminated; and if there are deviations in the manufacturing and assembly of the plates, the expanded part of the plate does not enter the receiving groove but directly contacts the plane of the receiving groove, and the horizontal expansion of the plate is blocked, and the expanded part will elongate in the vertical direction, making it more likely to occur plate short circuits.

[0008] Therefore, no matter which process is used currently, it is impossible to avoid the occurrence of short circuits between the positive and negative plates, and more suitable solutions need to be further developed.

Summary of the Invention

[0009] The present invention provides a horizontal lead-acid battery with a filler, which can limit the expansion of the plates to both sides, thereby avoiding short circuits caused by contact between the positive and negative active materials.

[0010] The present invention also provides an assembly method for the above horizontal lead-acid battery.

[0011] The technical solution of the present invention is as follows:

[0012] A horizontal lead-acid battery with a filler, comprising a battery housing and a battery electrode group composed of positive and negative plates and a separator. It is characterized in that a filler which is injected in a liquid form at normal temperature and transformed into a solid state after curing treatment is arranged around the positive and negative plates. This filler can fill all the plate gaps, tightly wrap the plates, limit the expansion of the plates, and only allow expansion in the direction perpendicular to the plate plane, avoiding short circuits between the positive and negative plates. Moreover, the extremely high assembly pressure of the horizontal battery limits the expansion of the active material, ensuring the integrity of the active material and greatly improving the service life of the horizontal lead-acid battery.

[0013] Further, the filler before curing is a resin, rubber, sodium alginate solution or asphalt with fluidity. The resin can be selected from silica sol or foamed polyurethane with fluidity. The above filler overcomes the solidification problem during the filling process and fundamentally improves the filling effect.

[0014] Further, isolating members for blocking the flow of liquid and / or gas between different battery electrode groups are arranged on both sides of the above battery cluster. The arrangement of the isolating members can prevent the leakage of liquid and gas between different battery electrode groups at the lead wires of the bipolar plates.

[0015] Further, isolating member positioning grooves are arranged at positions corresponding to the isolating members on the inner surfaces of the bottom plate, side plates and top cover of the above battery housing. The isolating member positioning grooves are beneficial for positioning when assembling the isolating members and can also be filled with sealant to completely seal the gap between the entire isolating member and the housing, achieving complete sealing between different cells.

[0016] Further, an injection hole for injecting liquid sealant that penetrates the bottom plate of the battery housing longitudinally is arranged on the above isolating member. A sealant accommodating groove for accommodating sealant is arranged at the upper end and / or lower end of the isolating member. A sealant storage cavity groove for the flow of sealant is arranged between the side wall of the isolating member and the side wall of the battery housing. After curing treatment, the injection hole, sealant accommodating groove, sealant storage cavity groove and isolating member positioning groove are all filled with sealant, further providing a sealing effect. It should be noted that the effects of the sealant and the above filler are different. Sealant sealing is part of the assembly. Before the battery formation, its purpose is to prevent liquid or gas leakage and short circuits between single cells; the filler injection is after the formation, and its function is to limit the expansion of the plates, prevent contact short circuits between the positive and negative plates, and extend the service life. Therefore, the sealant and the filler do not require the same substance and are mostly different in most cases.

[0017] Furthermore, an acid inlet hole for injecting acid or liquid filler is provided at the lower part of the side plate of the battery case, and an exhaust hole for exhausting gas when injecting acid or liquid filler is provided on the top cover of the battery case. Whether it is acid or liquid filler, it is injected through this hole, and the exhaust gas during this process is discharged through the exhaust hole. A vacuum device can also be used in this process to accelerate filling.

[0018] Furthermore, a rubber hole plug that cooperates with and seals the glue injection through hole is provided at the opening of the glue injection through hole of the above-mentioned horizontal lead-acid battery, so as to achieve better sealing and aesthetic effects.

[0019] Furthermore, the above-mentioned horizontal lead-acid battery maintains an assembly pressure of 100 KPa or more, and the top cover and side plate of the battery case are self-locked through the rebound force of the electrode group after being press-fitted. For traditional batteries, on the one hand, the assembly pressure is small, and on the other hand, the plastic shell has low strength and is not enough to limit the expansion of the positive and negative plates in the thickness direction, which easily causes the positive active material to soften and fall off after expansion; while the horizontal battery cluster has a large enough assembly pressure and a strong enough plastic shell, which limits the expansion of the active material and ensures the integrity of the active material.

[0020] The assembly method of the above-mentioned horizontal lead-acid battery with filler includes the following steps: after the horizontal lead-acid battery is formed, a liquid filler is injected into the battery at room temperature. After filling the entire internal space of the battery, a curing treatment is carried out to solidify the liquid filler.

[0021] Furthermore, the above-mentioned curing treatment is natural cooling and solidification, or heating and curing, or charging to cause charge neutralization effect, dehydration effect or bridging effect of the filler to coagulate and form a stable solid or gel.

[0022] Furthermore, during the process of injecting the liquid filler, the gas in the battery is discharged through the exhaust hole provided on the top cover of the battery case.

[0023] Furthermore, the separator is a strip-shaped structure composed of an elastic matrix and inserts wrapped inside the elastic matrix. The height of the strip-shaped structure is equivalent to the distance between the plates of the horizontal lead-acid battery. Positioning grooves for the separator are provided on the inner surfaces of the bottom plate, side plate, and top cover of the battery case corresponding to the separator. A glue-receiving groove that penetrates left and right for accommodating sealant is provided at the upper end and / or lower end of the strip-shaped structure. The elastic matrix and the inserts are provided with cooperating longitudinal glue injection through holes on the same longitudinal line. A glue storage cavity for the flow of sealant is provided between the side wall of the separator and the side wall of the battery case. An acid inlet hole for injecting acid or liquid filler is provided at the lower part of the side plate of the battery case, and an exhaust hole for exhausting gas when injecting acid or liquid filler is provided on the top cover of the battery case;

[0024] The assembly method includes the following steps:

[0025] Stack the separator, diaphragm, and battery plates in a fixed order inside the battery case, press-fit the top cover to lock it self-latchingly, and then inject glue through the glue injection through-hole to fill all the glue-containing grooves, glue injection through-holes, separator positioning grooves, and glue storage cavity grooves. After curing, all the separators and the lead wires sandwiched between the separators are connected into one body to complete the assembly;

[0026] Then, weld terminals to the positive and negative electrode lead-out ends of the battery, seal the end cover, and enter the formation stage; for the formation, during the activation charging process of the battery, the acid in the acid container enters the battery through the acid inlet hole at the lower part of the battery side plate, leaves the battery through the exhaust hole on the battery top cover and returns to the acid container to form a closed cycle. After the formation charging is completed, the acid in the single cell cavity of the battery, except for the part retained in the micropores of the diaphragm and the positive and negative plates, the rest is pumped back into the acid container through the acid inlet hole of the battery. Thus, a certain cavity is formed between the plate and the side wall of the battery case;

[0027] Inject a liquid filler through the acid inlet hole. The gas inside the battery is discharged through the exhaust hole. The filler fills the cavity between the plate and the side wall of the battery case, completely surrounds the positive and negative plates from all around. After curing, it is cleaned and packaged, and the finished battery is completed.

[0028] The beneficial effects of the present invention are as follows:

[0029] The present invention injects a filler that is liquid at normal temperature and turns into a solid after curing treatment inside the horizontal lead-acid battery; this filler can fill all the plate gaps, tightly wrap the plates, limit the expansion of the plates to both sides, and can only expand in the direction perpendicular to the plate plane, avoiding short-circuiting of the positive and negative plates. Moreover, the extremely high assembly pressure of the horizontal battery limits the expansion of the active material, ensuring the integrity of the active material, greatly improving the service life of the horizontal lead-acid battery; the assembly method of the present invention is reasonable, the steps are simple, and the sealing effect is good, which is beneficial to improving the overall performance of the battery and also improving the assembly efficiency of the horizontal lead-acid battery.

Description of the Drawings

[0030] Figure 1 It is a side sectional view of the horizontal lead-acid battery of Embodiment 1;

[0031] Figure 2 For Figure 1 An enlarged view of the partial A.

[0032] Annotation description: 1, battery case; 2, plate; 3, glue injection through-hole; 4, separator; 5, glue hole plug.

Detailed Embodiments

[0033] The following uses specific embodiments to further elaborate on the present invention in detail, but the present invention is not limited to the following specific embodiments.

[0034] The following embodiments are not intended to limit the scope of the present invention, nor are the steps described to limit their execution order. Any obvious improvements made by those skilled in the art based on existing common knowledge to the present invention are also within the scope of protection claimed by the present invention.

[0035] Example 1

[0036] A horizontal lead-acid battery with a filler, e.g. Figure 1 and Figure 2 As shown, it includes a battery casing 1, and a battery pole group consisting of a positive plate 2 (positive and negative plates) and a separator. Physical barriers formed by several separators 4 are set at both ends of each battery pole group, and all the pole plates 2 are wrapped with fillers.

[0037] The isolating member is a strip structure composed of an elastic matrix and an insert wrapped inside the elastic matrix. The height of the strip structure is equivalent to the spacing between the horizontal lead-acid battery plates. The inner surfaces of the bottom plate, side plate and top cover of the battery shell are provided with isolating member positioning grooves at positions corresponding to the isolating member (i.e., physical barrier). The upper end and / or lower end of the strip structure are provided with left-right through-holes for accommodating sealant. The elastic matrix and the insert are provided with matching longitudinal glue injection holes on the same longitudinal line. A glue storage cavity for the flow of sealant is provided between the side wall of the isolating member and the side wall of the battery shell. An acid inlet hole for injecting acid or liquid filler is provided at the lower part of the side plate of the battery shell, and an exhaust hole for exhausting gas when injecting acid or liquid filler is provided on the top cover of the battery shell.

[0038] The sealant is injected in liquid form at room temperature through the glue injection hole 3 set in the isolation member 4, gradually filling the glue containing groove, glue storage cavity, glue injection hole, and isolation member positioning groove, and then the glue hole plug 5 is covered on the top of the glue injection hole 3. After heating and curing treatment, it is converted into a solid state, and then cast-welded, the end cover is encapsulated, and electrified.

[0039] After the formation is completed, filler is injected from the acid injection hole to fill all the gaps between the plates 2 and solidify. Under the extremely high assembly pressure of the horizontal battery (100KPa and above), the expansion of the active material can be effectively limited, the short circuit of the positive and negative plates can be avoided, the integrity of the active material is ensured, and the life of the horizontal lead-acid battery is greatly improved.

[0040] During the acid and filler injection process, the gas inside the battery is discharged through the exhaust hole; this process can also be combined with vacuum equipment to accelerate the filling.

[0041] In this embodiment, the filler is silica sol, which is a dispersion of nanoscale silica particles in water or a solvent before curing, with a concentration of 5-20 wt%. After charging at 5 A for 20 hours, it polymerizes and settles into a gel due to the charge neutralization effect. During the charge and discharge process of the battery, the coagulation further deepens. After 50-100 charge and discharge cycles, as the moisture is lost, it becomes a solid with certain cracks.

[0042] The assembly process of the above horizontal lead-acid battery includes the following steps:

[0043] Stack the separator, diaphragm, and battery plates in a fixed order inside the battery case, press-fit the top cover to lock it self-locking, and then inject glue through the glue injection through-hole to fill all the glue-containing grooves, glue injection through-holes, separator positioning grooves, and glue storage cavity grooves. After curing, all the separators and the lead wires sandwiched between the separators are connected into one body;

[0044] Then weld the terminals from the positive and negative electrode lead-out ends of the battery, seal the end cover, and enter the formation stage; the formation is that during the activation charging process of the battery, the acid in the acid container enters the battery from the acid inlet hole at the lower part of the battery side plate, leaves the battery through the exhaust hole on the battery top cover and returns to the acid container to form a closed cycle. After the formation charging is completed, except for the part of the acid remaining in the micropores of the diaphragm and the positive and negative plates in the single cell cavity of the battery, the rest is pumped back into the acid container through the acid inlet hole of the battery, thereby forming a certain cavity between the plate and the side wall of the battery case;

[0045] Inject the liquid filler through the acid inlet hole, the gas inside the battery is discharged through the exhaust hole, the filler fills the cavity between the plate and the side wall of the battery case, completely surrounds the positive and negative plates from all around, and after curing, it is cleaned and packaged, and the battery finished product is completed.

[0046] Battery performance detection

[0047] Table 1 Self-discharge rate, cycle life, and swelling short-circuit conditions of the horizontal lead-acid battery in Example 1

[0048]

[0049] After filling the filler, the self-discharge and swelling short-circuit of the battery are improved, and the cycle life is significantly increased.

[0050] Example 2

[0051] In Example 2, the filler is a 1-10 wt% sodium alginate solution, which is a viscous paste before curing, has a certain fluidity after high-speed stirring and shearing, and is vacuum-pumped into the battery cavity. After charging at 5 A for 6 hours, due to the dehydration effect, it forms a jelly-like elastomer, and during the charge and discharge process of the battery, the elastomer further loses water and hardens.

[0052] Example 3

[0053] In the third embodiment, the filler is epoxy glue, which is a liquid with very low viscosity and good fluidity before curing, at a constant temperature of 60°C.

Claims

1. A horizontal lead-acid battery with a filler, comprising a battery housing and a battery electrode group composed of positive and negative plates and a separator, characterized in that, Around the positive and negative plates, there is a filler that is injected in a liquid form at room temperature and transformed into a solid state after curing treatment; On both sides of the battery cluster, there is a separator for blocking the flow of liquid and / or gas between different battery electrode groups; At positions corresponding to the separator on the inner surfaces of the bottom plate, side plates, and top cover of the battery case, separator positioning grooves are provided; On the separator, there is a vertically penetrating glue injection through-hole for injecting liquid sealant through the bottom plate of the battery case. At the upper end and / or lower end of the separator, there is a glue storage groove for accommodating the sealant. Between the side wall of the separator and the side wall of the battery case, there is a glue storage cavity for the sealant to flow. After curing treatment, the glue injection through-hole, glue storage groove, glue storage cavity, and separator positioning groove are all filled with sealant.

2. The horizontal lead-acid battery with a filler according to claim 1, characterized in that, Before curing, the filler is a resin, rubber, sodium alginate solution, or asphalt with fluidity.

3. The horizontal lead-acid battery with a filler according to claim 2, characterized in that, Before curing, the resin is silica sol or foamed polyurethane with fluidity.

4. The horizontal lead-acid battery with filler according to claim 1, characterized in that, At the lower part of the side plate of the battery case, there is an acid injection hole for injecting acid or liquid filler. On the top cover of the battery case, there is an exhaust hole for exhausting gas when injecting acid or liquid filler.

5. The horizontal lead-acid battery with a filler according to claim 1, characterized in that, At the opening of the glue injection through-hole of the horizontal lead-acid battery, there is a glue hole plug for sealing in cooperation with the glue injection through-hole.

6. The horizontal lead-acid battery with filler according to any one of claims 1-5, characterized in that, The horizontal lead-acid battery maintains an assembly pressure of 100 KPa or more, and after the top cover and side plate of the battery case are press-fitted, they are self-locked by the rebound force of the electrode group.

7. The assembling method of the horizontal lead-acid battery with fillers as claimed in claim 1, characterized in that Including the following steps: When the horizontal lead-acid battery is formed, inject a filler in a liquid form into the battery at room temperature. After filling the entire internal space of the battery, perform a curing treatment to cure the filler in a liquid form.

8. The assembling method of the horizontal lead-acid battery with filler according to claim 7, characterized in that, The curing treatment is natural cooling and solidification, or heat curing, or through charging to cause charge neutralization effect, dehydration effect, or bridging effect of the filler to coagulate and form a stable solid or gel.

9. The assembling method of the horizontal lead-acid battery with fillers according to claim 8, characterized in that, During the process of injecting the filler in a liquid form, the gas in the battery is discharged through the exhaust hole provided on the top cover of the battery case.

10. The assembling method of the horizontal lead-acid battery with filler according to claim 9, characterized in that, The separator is a strip-shaped structure composed of an elastic matrix and inserts wrapped inside the elastic matrix. The height of the strip-shaped structure is equivalent to the distance between the plates of the horizontal lead-acid battery. At positions corresponding to the separator on the inner surfaces of the bottom plate, side plates, and top cover of the battery case, separator positioning grooves are provided. At the upper end and / or lower end of the strip-shaped structure, there is a horizontally penetrating glue storage groove for accommodating the sealant. The elastic matrix and the inserts are provided with a vertically matching glue injection through-hole on the same longitudinal line. Between the side wall of the separator and the side wall of the battery case, there is a glue storage cavity for the sealant to flow. At the lower part of the side plate of the battery case, there is an acid injection hole for injecting acid or liquid filler. On the top cover of the battery case, there is an exhaust hole for exhausting gas when injecting acid or liquid filler; The assembly method includes the following steps: Stack the separator, diaphragm, and battery plates in a fixed order inside the battery case, press-fit the top cover to lock it self-latchingly, and then inject glue through the glue injection through-hole so that it fills all the glue-containing grooves, glue injection through-holes, separator positioning grooves, and glue storage cavity grooves. After curing, all the separators and the lead wires sandwiched between the separators are connected into one body to complete the assembly; Then, weld the terminals from the positive and negative electrode lead-out ends of the battery, seal the end cover, and enter the formation stage; the so-called formation is that during the activation charging process of the battery, the acid in the acid container enters the battery from the acid inlet hole at the lower part of the battery side plate, leaves the battery from the exhaust hole in the battery top cover and returns to the acid container to form a closed cycle. After the formation charging is completed, the acid in the single cell inner cavity of the battery, except for the part retained in the diaphragm and the micropores of the positive and negative plates, the rest is pumped back to the acid container through the acid inlet hole of the battery, thereby forming a certain cavity between the electrode plate and the side wall of the battery case; Inject the liquid material filler through the acid inlet hole, discharge the gas inside the battery through the exhaust hole, fill the cavity between the electrode plate and the side wall of the battery case with the filler, completely surround the positive and negative electrode plates from all around, clean and package after curing, and the battery finished product is completed.

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