CN109935787B - Bipolar plate and manufacturing method thereof - Google Patents
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- CN109935787B CN109935787B CN201910191292.4A CN201910191292A CN109935787B CN 109935787 B CN109935787 B CN 109935787B CN 201910191292 A CN201910191292 A CN 201910191292A CN 109935787 B CN109935787 B CN 109935787B
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Abstract
The invention provides a method for manufacturing a bipolar plate, which comprises the steps of 102, preparing a grid mesh capable of being coated with paste; 104, coating positive paste on a first partial area of the grid mesh to form a positive electrode area, coating negative paste on a second partial area of the grid mesh to form a negative electrode area, and not performing coating operation on a third partial area separating the first partial area and the second partial area in the grid mesh to form a vacant area, thereby obtaining a pole plate structure; step 106, carrying out curing treatment, pickling treatment and drying treatment on the electrode plate structure to obtain a bipolar plate; the bipolar plate obtained by the manufacturing method can effectively improve the charge and discharge performance of the battery and prolong the service life of the battery when being applied to the lead-acid storage battery.
Description
Technical Field
The invention belongs to the technical field of electrochemical cells, and particularly relates to a bipolar plate and a manufacturing method thereof.
Background
Electrochemical cells, particularly lead acid batteries, are widely used in various fields such as automobiles, and are capable of storing energy and delivering the energy to a target object in the form of electric energy. The lead-acid battery mainly generates electrochemical reaction between a lead-acid electrode and electrolyte such as dilute sulfuric acid, and the like, thereby generating transmission current. After the electrolyte such as dilute sulfuric acid is poured into the battery, the temperature inside the battery can be rapidly increased due to the exothermic reaction between the dilute sulfuric acid and the active material such as lead oxide in the lead-acid electrode, and the high-temperature environment inside the battery can accelerate the formation of reactants such as sulfate on the battery plate, which in turn can reduce the concentration of the dilute sulfuric acid inside the battery. Therefore, the performance of the battery can be affected by a high-temperature environment formed after dilute sulfuric acid is poured into the battery, specifically, a thicker sulfate layer can be deposited on the surface of the polar plate under the high-temperature environment, so that the migration efficiency of the dilute sulfuric acid to the inside of the polar plate can be improved, the inside of the polar plate is a lower acid concentration environment, and the lead dissolving process in the grid of the polar plate can be accelerated under the lower acid concentration environment; in addition, after the dilute sulfuric acid is poured into the battery, a large temperature difference exists between different battery units, the large temperature difference can seriously affect the formation of the active materials in the polar plate, and the sulfate deposited on the surface of the polar plate can further increase the temperature of the electrolyte and hinder the formation of the active materials in the polar plate, so that the different battery units can finally show remarkable nonuniformity in the formation of the active materials. Also, lead-acid batteries are generally operated in a sealed state, and the sealed state and high-temperature environment inside the batteries can cause dilute sulfuric acid to penetrate through the separators on the surfaces of the plates and cause dendritic short-circuit, thereby resulting in the effective operation of the batteries. Therefore, the normal work of the lead-acid storage battery can be seriously influenced by the high-temperature environment generated in the lead-acid storage battery after the lead-acid storage battery is filled with dilute sulfuric acid.
At present, bipolar plates used in lead-acid batteries are all of a lead substrate as a basic structure, a positive paste is coated on one surface of the lead substrate, and a negative paste is coated on the other opposite surface of the lead substrate, and the bipolar plates of the above structure cannot resist the influence caused by the high-temperature environment inside the battery, and have a series of problems that the lead substrate is easily corroded to cause short circuit inside the battery, and the adhesion between an electrode active material and the flat surface of the lead substrate is poor. Therefore, the bipolar plate structure in the prior art cannot effectively improve the working efficiency and the working stability of the lead-acid battery.
Disclosure of Invention
In a lead-acid storage battery, the existing bipolar plate structure cannot be well adapted to a high-temperature environment formed after dilute sulfuric acid is filled in the battery, so that the bipolar plate is easily corroded by the dilute sulfuric acid in the electrochemical reaction process, the adhesion between the electrode paste and the bipolar plate is poor, an active material in the electrode paste is easy to fall off in the electrochemical reaction process, meanwhile, the existing bipolar plate structure has high internal resistance, the formation degree of the active materials of the electrode paste in different areas in the bipolar plate structure is not uniform, and the charge-discharge performance of the lead-acid storage battery is severely restricted and the service life of the lead-acid storage battery is shortened.
Aiming at the defects in the prior art, the invention provides a method for manufacturing a bipolar plate, which takes a grid structure as a basic frame, coats electrode paste on different parts of the grid structure, then carries out a series of different treatment processes such as curing treatment, pickling treatment, drying treatment and the like on the electrode paste, and improves the curing performance and structural morphology characteristics of an active material in the electrode paste by changing the implementation sequence of the different treatment processes and adjusting the process parameters corresponding to each treatment process, thereby finally effectively improving the charge and discharge performance of a lead-acid storage battery and prolonging the service life of the lead-acid storage battery.
The invention provides a method for manufacturing a bipolar plate, wherein the bipolar plate comprises a grid mesh, and the method for manufacturing the bipolar plate is characterized by sequentially comprising the following steps of:
102, preparing a grid mesh capable of being coated with paste;
104, coating a positive paste on a first partial area of the grid mesh to form a positive area, coating a negative paste on a second partial area of the grid mesh to form a negative area, and not performing coating operation on a third partial area separating the first partial area and the second partial area in the grid mesh to form a vacant area, so as to obtain a pole plate structure;
step 106, carrying out curing treatment, pickling treatment and drying treatment on the polar plate structure to obtain a bipolar plate; further, the operation of the device is as follows;
further, in the step 102, the grid is formed by processing any one of basic materials of metallic lead, lead-based alloy, carbon fiber and carbon fiber composite metal material;
further, in step 102, the grid is formed by at least one of weaving, casting, stamping, forging, punching, drawing, or rolling the base material;
further, in the step 104, preparing the positive paste and the negative paste, wherein the positive paste and the negative paste are prepared by mixing an active material obtained by lead oxide, lead sulfate, sulfuric acid, a plurality of additives, and water in a predetermined ratio;
further, the content of the lead sulfate in the active material is less than 15%;
further, in step 106, performing curing treatment, pickling treatment, and drying treatment on the plate structure, specifically, performing curing treatment, first drying treatment, pickling treatment, and second drying treatment on the plate structure in sequence;
further, in step 106, performing curing treatment, pickling treatment, and drying treatment on the plate structure, specifically performing pickling treatment, curing treatment, and third drying treatment on the plate structure in sequence;
further, the pickling treatment specifically comprises the step of continuously soaking the polar plate structure in a dilute sulfuric acid solution for a preset time, wherein the specific gravity of sulfuric acid and water in the dilute sulfuric acid solution is 1.1-1.3, and the temperature of the dilute sulfuric acid solution is 20-45 ℃;
further, after the treatment of the step 106, the content of lead sulfate in the positive paste or the active material corresponding to the negative paste is 20% to 40%;
further, in the step 106, the method further includes covering the upper surface and the lower surface of the paste corresponding to the positive electrode area and the negative electrode area of the bipolar plate with separator paper.
Compared with the prior art, the manufacturing method of the bipolar plate has the advantages that the positive paste and the negative paste are respectively arranged in two different areas which are isolated from each other, and the two different areas are not respectively positioned on two opposite surfaces of the bipolar plate but simultaneously cover the upper surface and the lower surface of the bipolar plate; in addition, the bipolar plate adopts the grid structure as the basic structure of the polar plate, the grid structure has various grid distribution shapes, and the different grid distribution shapes can correspondingly improve the adhesion stability between the positive paste and the negative paste and the grid structure and effectively reduce the internal resistance of the bipolar plate, so that the lead-acid storage battery with the bipolar plate has good charge and discharge performance and longer service life, and the overall working performance of the lead-acid storage battery is further improved.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a schematic structural diagram of a bipolar plate manufacturing method according to the present invention.
Fig. 2 is a schematic structural diagram of a bipolar plate formed by the bipolar plate manufacturing method provided by the invention.
Fig. 3 is a schematic structural diagram of a grid used in the method for manufacturing a bipolar plate according to the present invention.
The numerical designations in the drawings are respectively: 1: positive paste, 2: negative electrode paste, 3: separator paper, 4: grid mesh, 5: first partial region, 6: second partial region, 7: a third partial area.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1, a schematic structural diagram of a method for manufacturing a bipolar plate according to an embodiment of the present invention is shown; correspondingly, fig. 2 is a schematic structural diagram of a bipolar plate manufactured by the bipolar plate manufacturing method. As can be seen from fig. 2, the bipolar plate comprises a positive paste 1, a negative paste 2, a separator paper 3 and a grid 4; the grid 4 forms a basic structure of the bipolar plate, the positive paste 1 is coated on a first partial area 5 of the grid 1, the negative paste 2 is coated on a second partial area 6 of the grid 4, a third partial area 7 is arranged between the first partial area 5 and the second partial area 6 at an interval, and the third partial area 7 can completely separate the first partial area 5 from the second partial area 6, so that the positive paste 1 on the first partial area 5 cannot be in direct contact with the negative paste 2 on the second partial area 6, and a short circuit condition inside the bipolar plate is avoided. Preferably, the first partial region 5, the second partial region 6 and the third partial region 7 each belong to a different grid structure region of the grid 4; preferably, the third partial region 7 can be located between the first partial region 5 and the second partial region 6, in order to achieve a complete separation of the first partial region 5 and the second partial region 6.
In order to obtain a bipolar plate having the structure shown in fig. 2, the bipolar plate is fabricated by a method comprising the steps of:
102, preparing a grid mesh capable of being coated with paste;
104, coating a positive paste on a first partial area of the grid mesh to form a positive area, coating a negative paste on a second partial area of the grid mesh to form a negative area, and not performing coating operation on a third partial area separating the first partial area and the second partial area in the grid mesh to form a vacant area, so as to obtain a pole plate structure;
and 106, carrying out curing treatment, pickling treatment and drying treatment on the polar plate structure to obtain a bipolar plate.
Wherein, in the step 102, the grid can preferably adopt a grid structure as shown in fig. 3. Preferably, the material of the grid mesh can be any one of metal lead, lead-based alloy, carbon fiber and carbon fiber composite metal material; preferably, the grid is formed by weaving, casting, stamping, forging, punching, wire drawing or rolling.
Specifically, the grid mesh may have a screen mesh structure disposed in a staggered manner, and compared with the planar substrate structure in the prior art, the contact area between the screen mesh structure and the electrode paste is significantly larger than that between the planar substrate structure and the electrode paste, and the significant increase of the contact area makes the adhesion between the screen mesh structure and the electrode paste also significantly better than that between the planar substrate structure and the electrode paste under the condition of the same size. Compared with the prior art, the silk screen structure has the advantages that the positive active material and the negative active material are coated on the same silk screen structure at the same time, and the silk screen structure is obviously different from the prior art that the positive active material and the negative active material are respectively coated on two independent silk screen structure substrates. In addition, when the positive paste or the negative paste is coated on the wire mesh structure of the grid mesh, the positive paste or the negative paste can penetrate into the self gap inside the wire mesh structure, and after the treatment of the subsequent manufacturing process, the positive paste and the negative paste can be firmly attached to the wire mesh structure.
Accordingly, the grid may comprise a first partial region, a second partial region and a third partial region; preferably, the third partial region can be located between the first partial region and the second partial region; preferably, the third partial region can completely separate the first partial region from the second partial region. The screen structure corresponding to the first partial area or the second partial area can be coated with positive paste or negative paste respectively, and the screen structure corresponding to the third partial area is not coated with any paste and becomes a vacant area. Preferably, the screen structures covered by the first and second part-areas each have a first coverage area S1, and the screen structures covered by the third part-area have a second coverage area S2, wherein S1> S2. Experiments show that the size of the first coverage area S1 affects the reaction efficiency between the corresponding positive or negative electrode paste and the electrolyte on the second partial area of the first partial area, but the reaction efficiency is higher when the first coverage area S1 is larger, and preferably, the reaction efficiency can be optimized when the first coverage area S1 and the whole area S of the grid satisfy 40% S1% S95% S.
Correspondingly, the wire mesh structures of the first partial region and of the second partial region can have a first wire mesh size P1, and the wire mesh structures of the third partial region can have a second wire mesh size P2, the respective wire mesh structures of the first partial region, of the second partial region and of the third partial region having a constant mesh size. The first screen size P1 is preferably greater than the second screen size P2; preferably, in the first and second partial regions, the corresponding screen mesh size may be 2-5mm 3-8mm, and in the third partial region, the corresponding screen mesh size may be 2-5mm 8-15 mm.
In addition, the wire mesh structure can not be limited to have different shapes, and the wire mesh structures with different shapes can directly influence the internal resistance condition of the corresponding bipolar plate; preferably, the wire mesh structure may have a structure formed by interlacing warp and weft; preferably, the warp and weft threads are interlaced with each other to form a regular or irregular mesh structure, wherein the regular mesh structure has a uniform distribution of rectangular or square mesh openings and the irregular mesh structure has a non-uniform distribution of mesh openings, such as irregular polygonal mesh openings. The research shows that the wire mesh structure with the irregular shape has lower internal resistance value compared with the wire mesh structure with the regular shape, which is beneficial to integrally reducing the internal resistance value of the bipolar plate, and the lower the internal resistance value of the bipolar plate is, the better the charge-discharge performance of the corresponding lead-acid storage battery is, and the higher the electric energy conversion efficiency of the electrochemical reaction is; specifically, on the premise that the grids have the same area size, compared with the grids with a regular wire mesh structure, the grids with an irregular wire mesh structure have the internal resistance value which can be effectively reduced by 30% -40%, and the grids have a remarkable effect of improving the electrical performance of the bipolar plate.
Furthermore, in order to enable the electrode paste to be firmly attached to the grid, in addition to reducing the size of the screen structure corresponding to the first area portion and the second area portion, a plurality of randomly distributed barb structures may be arranged on the screen structure. The barb structures can be distributed on the mutually staggered warps and wefts in the grid mesh. The presence of the barb structures increases the roughness and surface area of the grid surface, which enables the electrode paste to be adhesively bonded to the screen structure to the maximum extent when the electrode paste is applied to the grid surface, and ultimately improves the adhesion between the electrode paste and the screen structure.
In step 104, before the positive paste and the negative paste are applied to the first partial area and the second partial area of the grid respectively, the positive paste and the negative paste are prepared. Specifically, the positive paste and the negative paste each include an active material capable of electrochemically reacting with the electrolyte, such as dilute sulfuric acid, to produce a corresponding battery current and voltage. Preferably, the active material is prepared by mixing lead oxide, lead sulfate, sulfuric acid, a plurality of additives and water according to a predetermined proportion to obtain an initial mixture and then performing specific process treatment; preferably, the specific process treatment may include, but is not limited to, at least one of mixing, stirring, standing, aging, and filtering. Alternatively, in the initial mixture corresponding to the active material, the lead oxide may be present in an amount of 50% to 85% by weight, the lead sulfate may be present in an amount of 1% to 15% by weight, the sulfuric acid may be present in an amount of 3% to 8% by weight, the plurality of additives may be present in an amount of 2% to 5% by weight, and the water may be present in an amount of 10% to 30% by weight. Preferably, the weight ratio of the lead sulfate in the final active material obtained after the initial mixture is subjected to the specific process is increased to 20-40%; preferably, substantially no free sulfuric acid is present in the final active material. By way of comparison, it has been found that, when the lead sulphate is present in the active material in a proportion of more than 15% by weight of the corresponding initial mixture, the content of free sulphuric acid in the corresponding final active material will rise significantly, whereas when the lead sulphate is present in the initial mixture of active materials in a proportion of 1% to 15% by weight, the content of free sulfuric acid in the corresponding active material will be negligible, since in the final active material, the high content of free sulfuric acid directly affects the efficiency of the electrochemical reaction between the positive paste or the negative paste and the electrolyte such as dilute sulfuric acid, and in short, the lower the free sulfuric acid content in the final active material, the higher the efficiency of the electrochemical reaction between the positive paste or negative paste and the electrolyte, and conversely, the higher the content of free sulfuric acid in the final active material, the lower the efficiency of the electrochemical reaction between the positive paste or negative paste and the electrolyte. Therefore, the weight ratio of the initial mixture corresponding to the active material to the final active material in the lead sulfate electrolyte is set to effectively improve the electrochemical reaction efficiency between the electrode paste and the electrolyte, so that the charge and discharge performance of the lead-acid storage battery is improved.
In addition, when selecting and determining the materials of the positive paste and the negative paste in the bipolar plate, the indexes of the alternative materials are obtained through experiments according to different factors such as the conductivity, heat dissipation, stability, processability, high temperature resistance, production period, fire resistance, air permeability and production cost of the materials, and are digitalized, so that a corresponding matrix Y is obtained
In the matrix Y, bstThe index value corresponding to the t-th candidate material of the s-th index, and bjnThe index value is the index value corresponding to the nth candidate material of the jth index. In order to improve the reliability of comparison between different index values, it is necessary to normalize the index values by the following equation:
in this formula, b* stIs b isstThe corresponding value after the normalization process is performed,
is the s indexMean value of (a)sIs the variance of the s-th index for each bstCan be obtained by corresponding normalization processing* stThereby obtaining a new matrix Y*. To obtain a new matrix Y*The correlation of the medium indexes needs to calculate the covariance of each index and obtain another new matrix C
Wherein cov (b)j *，bj *) Is the b thj *Individual index and bj *The covariance between the indexes, j is the number of rows and columns of the matrix C, and the value of the covariance between the indexes is used to represent the correlation magnitude between the indexes. In order to ensure that each index of the principal component obtained by each covariance is orthogonal pairwise, an eigenvalue and an eigenvector of the covariance matrix C are required to be solved, and the solving step of the eigenvalue and the eigenvector of the principal component specifically comprises the following steps:
|C-λE|＝0
wherein C is covariance matrix, E is unit matrix, the lambda solved by the above-mentioned characteristic equation is the required characteristic vector, and the solved maximum eigenvalue lambda is0Substituting the above characteristic equation to calculate the corresponding basic solution, if the value of the basic solution is:
P＝(p1,p2,…pj)
it may be determined that the scoring criteria for the candidate material is:
y＝p1x1+p2x2+…+pjxj
where y is the final score of the candidate material and xiThe value of the ith index of the candidate material after normalization processing is adopted, and finally the candidate material with the maximum y value is taken as the finally determined material.
Further, in the step 104, after the positive paste and the negative paste are prepared, the positive paste and the negative paste may be respectively coated on the grid structures corresponding to the first partial area and the second partial area through a specific coating process, and meanwhile, no coating operation is performed on the grid structure corresponding to the third partial area to make the third partial area become a vacant area, so as to isolate the positive paste and the negative paste from contacting each other.
In step 106, the curing, pickling, and drying processes performed on the plate structure specifically include: (A) sequentially carrying out curing treatment, first drying treatment, pickling treatment and second drying treatment on the polar plate structure, or (B) sequentially carrying out two different treatment process flows of pickling treatment, curing treatment and third drying treatment on the polar plate structure. In fact, the electrochemical performance and morphological structure characteristics of the positive paste and the negative paste are affected differently by adjusting the sequence and times of the curing treatment, the pickling treatment and the drying treatment of the plate structure and the treatment parameters in each treatment step. Practice proves that through the two different treatment process flows of the (A) or the (B) and the corresponding treatment parameter adjustment, the electrode paste with better electrochemical performance and morphological structure characteristics can be obtained.
Further, the treatment process flow (a) may specifically include: (1) under the conditions of specific humidity H and temperature T1, the polar plate structure is placed in a standing mode for a preset time period T1 to realize solidification of the polar plate structure, wherein the humidity H, the temperature T1 and the preset time period T1 respectively meet the conditions that H is more than or equal to 30% and less than or equal to 90%, T1 is more than or equal to 25 ℃ and less than or equal to 35 ℃, and T1 is more than or equal to 45min and less than or equal to 120 min; (2) the polar plate structure is placed at a specific temperature T2 to be dried for a preset time period T2, wherein the temperature T2 and the specific time period T2 respectively meet the conditions that T2 is more than or equal to 50 ℃ and less than or equal to 85 ℃ and T2 is more than or equal to 30min and less than or equal to 60 min; (3) the pole plate structure is placed in a dilute sulfuric acid solution with a specific temperature T3 and a specific gravity R1 for soaking for a preset time period T3, wherein the preset time period T3, the temperature T3 and the specific gravity R1 respectively meet the conditions that T3 is not less than 1min and not more than 10min, T3 is not less than 20 ℃ and not more than 45 ℃, R1 is not less than 1.300 and not more than 1.100, and particularly, T3 can be preferably set to be 27 ℃; (4) and (3) placing the polar plate structure at a specific temperature T4 to carry out drying treatment for a preset time period T4, wherein the temperature T4 and the specific time period T4 respectively meet the conditions that T4 is more than or equal to 60 ℃ and less than or equal to 90 ℃, and T4 is more than or equal to 60min and less than or equal to 300 min. After the series of processes, the weight ratio of the lead sulfate in the active materials corresponding to the positive paste and the negative paste is 20-40%, and the active materials basically do not contain free sulfuric acid.
Further, the treatment process flow (B) may specifically include: (1) the pole plate structure is placed in a dilute sulfuric acid solution with a specific temperature T5 and a specific gravity R1 for soaking for a preset time period T5, wherein the preset time period T5, the temperature T5 and the specific gravity R1 respectively meet the conditions that T5 is not less than 1min and not more than 10min, T5 is not less than 20 ℃ and not more than 45 ℃, R1 is not less than 1.300 and not more than 1.100, and particularly, T5 can be preferably set to be 27 ℃; (2) under the conditions of specific humidity H and temperature T6, the polar plate structure is placed in a standing mode for a preset time period T6 to realize solidification of the polar plate structure, wherein the humidity H, the temperature T6 and the preset time period T6 respectively meet the conditions that H is more than or equal to 30% and less than or equal to 90%, T6 is more than or equal to 25 ℃ and less than or equal to 35 ℃, and T6 is more than or equal to 45min and less than or equal to 120 min; (3) the polar plate structure is placed at a specific temperature T7 to be dried for a preset time period T7, wherein the temperature T7 and the specific time period T7 respectively meet the conditions that T7 is more than or equal to 60 ℃ and less than or equal to 90 ℃, and T7 is more than or equal to 60min and less than or equal to 300 min; or the temperature T7 and the specific time T7 can respectively meet the conditions that the temperature T7 is more than or equal to 50 ℃ and less than or equal to 90 ℃ and the temperature T7 is more than or equal to 60min and less than or equal to 300 min. After the series of processes, the weight ratio of the lead sulfate in the active materials corresponding to the positive paste and the negative paste is 20-40%, and the active materials do not contain free sulfuric acid basically.
In addition, in the step 106, the method further includes covering the upper surface and the lower surface of the paste corresponding to the positive electrode region and the negative electrode region of the bipolar plate with separator paper. The diaphragm paper can cover the upper surface and the lower surface of the positive paste and the lower surface of the negative paste respectively, so that the positive paste and the negative paste are prevented from being completely exposed to electrolyte environments such as dilute sulfuric acid and the like. Because the bipolar plate needs to be completely immersed in electrolyte such as dilute sulfuric acid in the working process of the lead-acid storage battery, the electrolyte can generate electrochemical reaction with the positive paste and the negative paste, if the positive paste and the negative paste are completely exposed in the electrolyte environment, the positive paste and the negative paste can be structurally loosened along with the generation of the electrochemical reaction and can possibly fall off from the grid mesh, and the efficiency of the electrochemical reaction can be greatly influenced. If the positive paste or the negative paste falls off from the grid, the grid structure is exposed to an electrolyte environment such as dilute sulfuric acid, and the electrolyte such as dilute sulfuric acid has strong corrosivity to the grid, and the grid structure is easily corroded by the electrolyte such as dilute sulfuric acid along with the lapse of electrochemical reaction time, and finally the bipolar plate works effectively. Therefore, the diaphragm paper covers the upper surface and the lower surface of the positive paste and the negative paste, and the integrity of the self-curing structures of the positive paste and the negative paste can be effectively maintained, so that the phenomena that the curing structures of the positive paste and the negative paste are damaged and loosened are avoided, and the service life of the bipolar plate in an electrolyte environment such as dilute sulfuric acid can be effectively prolonged. Preferably, the separator paper may be made of a non-conductive material, so that a short circuit phenomenon may be prevented from occurring inside the bipolar plate, thereby maintaining a normal operation state of the bipolar plate. Preferably, the thickness of the diaphragm paper can be 0.1mm-2mm, and the thickness of the diaphragm paper can be set to ensure that the diaphragm paper has good mechanical strength and effectively improve the coverage protection of the diaphragm paper to the paste.
In addition, the bipolar plate can be regarded as an RC parallel circuit formed by a capacitor and a resistor, and the discharge principle of the capacitor can be known as follows:
in the above formula, Uc(T) is the voltage across the capacitor after a discharge time T, U0The initial voltage before the capacitor is not discharged, R is the corresponding resistance value in the RC parallel circuit, e is a natural base number, C is the corresponding capacitance value in the RC parallel circuit, and the capacitance value C meets the requirement
In the above formula, k is a unit conversion factor and is a dielectric number, s is a facing area of the capacitor plate, and d is a distance between the bipolar plates.
In order to compensate for the defect that the discharge rate of the bipolar plate is increased due to the decrease of the dielectric number caused by the existence of the grid mesh in the bipolar plate, the discharge rate can be corrected by changing the distance between the bipolar plates, but the requirement that the discharge speed of the bipolar plate is not too fast is also considered, and the specific adjustment formula of the distance d (T) between the bipolar plates is as follows:
in the above formula, d (T) is the distance between the bipolar plates of the capacitor discharge time T, H is a unit adjustment number and the discharge rate of the bipolar plates can be changed by changing the value of the unit adjustment number H, d0Is the initial distance between the bipolar plates,0the initial dielectric constant, and (T) the dielectric constant of the capacitor discharge time T. Substituting the formula into the discharge principle correlation formula to obtain:
it can be seen that the effect of the increased discharge rate due to the addition of the grid in the bipolar plate can be mitigated by the above adjustment, and the service life of the bipolar plate can also be increased.
It can be seen from the above embodiments that the manufacturing method of the bipolar plate is to arrange the positive paste and the negative paste in two different areas separated from each other, respectively, and the two different areas are not located on two opposite surfaces of the bipolar plate, but cover the upper and lower surfaces of the bipolar plate at the same time; in addition, the bipolar plate adopts the grid structure as the basic structure of the polar plate, the grid structure has various grid distribution shapes, and the different grid distribution shapes can correspondingly improve the adhesion stability between the positive paste and the negative paste and the grid structure and effectively reduce the internal resistance of the bipolar plate, so that the lead-acid storage battery with the bipolar plate has good charge and discharge performance and longer service life, and the overall working performance of the lead-acid storage battery is further improved.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (10)
1. A method for manufacturing a bipolar plate, the bipolar plate comprises a grid mesh, and the method for manufacturing the bipolar plate sequentially comprises the following steps:
102, preparing a grid mesh capable of being coated with paste;
104, coating a positive paste on a first partial area of the grid mesh to form a positive area, coating a negative paste on a second partial area of the grid mesh to form a negative area, and not performing coating operation on a third partial area separating the first partial area and the second partial area in the grid mesh to form a vacant area, so as to obtain a pole plate structure;
step 106, carrying out curing treatment, pickling treatment and drying treatment on the polar plate structure to obtain a bipolar plate;
the grid mesh is provided with a wire mesh structure which is arranged in a staggered manner; the silk screen structure is provided with a plurality of barb structures which are distributed randomly;
the first partial area has a first covering area S1, and the first covering area S1 and the whole area S of the grid meet 40% S1S 95% S;
and
when determining the materials of the positive paste and the negative paste in the bipolar plate, the materials need to be selected according to the indexes of at least one factor of conductivity, heat dissipation, stability, processability, high temperature resistance, production period, fire prevention and air permeability and production cost of alternative materials;
the selection steps are specifically as follows:
index numerating the index of the at least one factor to obtain a corresponding matrix Y
In the matrix Y, bstThe index value corresponding to the t type candidate material of the s index, bjnThe index value corresponding to the nth candidate material of the jth index;
to b isstCarrying out standardization processing, wherein a formula corresponding to the standardization processing is as follows:
in this formula, bstIs b isstThe corresponding value after the normalization process is performed,
is the mean value of the s-th index, σsIs the variance of the s-th index for each bstCan be normalized to obtain bst；
Calculating the covariance of each index and obtaining a covariance matrix C
Cov (bj, bj) is a covariance between bj indexes and bj indexes, j is the number of rows and columns of the matrix C, and a value of the covariance between each index is used to represent a correlation magnitude between each index;
solving an eigenvector of the covariance matrix C;
|C-λE|＝0
wherein C is a covariance matrix, E is an identity matrix, λ solved by | C- λ E | ═ 0 is a required eigenvector, the solved maximum eigenvalue λ 0 is substituted into | C- λ E | ═ 0, a corresponding basic solution coefficient is calculated, and if the value of the basic solution coefficient is:
P＝(p1,p2,…pj)
it may be determined that the scoring criteria for the candidate material is:
y＝p1x1+p2x2+…+pjxj
where y is the final score of the candidate material, xiThe value of the ith index of the candidate material after the normalization processing is carried out, and finally the candidate material with the maximum y value is taken as the finally determined material.
2. The method of making the bipolar plate of claim 1, wherein: in step 102, the grid is formed by processing any one of basic materials of metallic lead, lead-based alloy, carbon fiber and carbon fiber composite metal material.
3. The method of manufacturing a bipolar plate as set forth in claim 2, wherein: in step 102, the grid is formed by at least one of weaving, casting, stamping, forging, punching, drawing, or rolling the base material.
4. The method of manufacturing a bipolar plate as set forth in claim 1, wherein: in the step 104, the method further includes preparing the positive paste and the negative paste, wherein the positive paste and the negative paste are made by mixing an active material obtained by lead oxide, lead sulfate, sulfuric acid, a plurality of additives, and water in a predetermined ratio.
5. The method of manufacturing a bipolar plate as set forth in claim 4, wherein: the weight ratio of the lead sulfate in the active material is less than 15%.
6. The method of manufacturing a bipolar plate as set forth in claim 1, wherein: in step 106, the curing, pickling, and drying of the plate structure are specifically performed by sequentially performing the curing, first drying, pickling, and second drying on the plate structure.
7. The method of manufacturing a bipolar plate as set forth in claim 1, wherein: in step 106, the curing, pickling, and drying of the plate structure are specifically performed by sequentially performing pickling, curing, and third drying of the plate structure.
8. The method of manufacturing a bipolar plate according to claim 6 or 7, wherein: the pickling treatment is to soak the polar plate structure in a dilute sulfuric acid solution continuously for a preset time, wherein the specific gravity of sulfuric acid and water in the dilute sulfuric acid solution is 1.1-1.3, and the temperature of the dilute sulfuric acid solution is 20-45 ℃.
9. The method of manufacturing a bipolar plate as set forth in claim 4, wherein: after the treatment of the step 106, the weight ratio of the lead sulfate in the active material corresponding to the positive paste or the negative paste is 20-40%.
10. The method of manufacturing a bipolar plate as set forth in claim 1, wherein: in the step 106, the method further includes covering the upper surface and the lower surface of the paste corresponding to the positive electrode area and the negative electrode area of the bipolar plate with separator paper.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101641606A (en) * | 2007-03-23 | 2010-02-03 | 株式会社丰田中央研究所 | State estimating device of secondary battery |
| CN102470771A (en) * | 2009-07-01 | 2012-05-23 | 丰田自动车株式会社 | Control system of vehicle |
| WO2016033479A1 (en) * | 2014-08-29 | 2016-03-03 | The Regents Of The University Of Michigan | Bulk force in a battery pack and its application to state of charge estimation |
| CN107765323A (en) * | 2017-09-25 | 2018-03-06 | 成都理工大学 | A kind of metallogenic prognosis method based on ASTER satellite datas |
| CN108549789A (en) * | 2018-04-19 | 2018-09-18 | 中南大学 | A kind of integrated modelling approach of tertiary cathode material feed proportioning system |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FI77543C (en) * | 1985-12-19 | 1989-03-10 | Neste Oy | ACKUMULATOR. |
| US4964878A (en) * | 1988-06-01 | 1990-10-23 | Electrosource, Inc. | Lead-acid rechargeable storage battery |
| JPH04341766A (en) * | 1991-05-18 | 1992-11-27 | Japan Storage Battery Co Ltd | Spiral type closed storage battery |
| CN1193449C (en) * | 2002-04-03 | 2005-03-16 | 北京世纪千网电池技术有限公司 | Lead-acid accumulator with coil structure |
| RU2299501C1 (en) * | 2006-01-11 | 2007-05-20 | Ермаков Сергей Алексеевич | Lead storage battery |
| CN102035032B (en) * | 2009-09-24 | 2012-09-19 | 烟台金潮宇科蓄电池有限公司 | Storage battery for golf cart and manufacturing method thereof |
| CN103035884B (en) * | 2012-12-13 | 2014-11-05 | 天能电池集团有限公司 | Method for pretreating raw polar plates for internal formation |
| CN105552314B (en) * | 2015-12-08 | 2017-09-26 | 哈尔滨工业大学 | A kind of preparation method of high reliability bipolar plates for bipolarity lead accumulator |
| US20180246173A1 (en) * | 2017-02-28 | 2018-08-30 | Honeywell International Inc. | Online determination of model parameters of lead acid batteries and computation of soc and soh |
| CN107768594A (en) * | 2017-10-19 | 2018-03-06 | 广州倬粤动力新能源有限公司 | A kind of storage battery production technological process |
-
2019
- 2019-03-14 CN CN201910191292.4A patent/CN109935787B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101641606A (en) * | 2007-03-23 | 2010-02-03 | 株式会社丰田中央研究所 | State estimating device of secondary battery |
| CN102470771A (en) * | 2009-07-01 | 2012-05-23 | 丰田自动车株式会社 | Control system of vehicle |
| WO2016033479A1 (en) * | 2014-08-29 | 2016-03-03 | The Regents Of The University Of Michigan | Bulk force in a battery pack and its application to state of charge estimation |
| CN107765323A (en) * | 2017-09-25 | 2018-03-06 | 成都理工大学 | A kind of metallogenic prognosis method based on ASTER satellite datas |
| CN108549789A (en) * | 2018-04-19 | 2018-09-18 | 中南大学 | A kind of integrated modelling approach of tertiary cathode material feed proportioning system |
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