Nickel-metal hydride battery positive electrode powder material and preparation method of nickel-metal hydride battery

[0032] The invention also provides a method for preparing a nickel-hydrogen battery, which is specifically implemented according to the following steps:

[0033] Step 1: Weigh the components required for the positive electrode of the Ni-MH battery,

[0034] Weigh 35%~60% of spherical Ni(OH) according to mass percentage 2 , 35%~62% cobalt-coated spherical Ni(OH) 2 , 2.5% to 6% CoO powder, 0.5% to 1.0% binder, the total mass percentage of the above components is 100%, and the weighed CoO powder is passed through a 100 mesh sieve for use. The binder is PT powder;

[0035] Step 2: Mix the components weighed in step 1 and manually stir until the CoO powder and binder are not visible to the naked eye;

[0036] Step 3: Add the mixed powder prepared in step 2 into the powder mixer, start the revolution switch and forced stirring switch to mix the powder, and the powder mixing time is 2h to 3h to obtain the positive electrode powder. The powder mixer is a V-shaped Powder mixer

[0037] Step 4: Fill the positive electrode powder prepared in step 3 into the foamed nickel matrix with the printed tabs, use a high-precision brush for uniform and precise filling, roll it into a sheet, and press the roll into a sheet of foam The nickel substrate is cut into positive plates;

[0038] Step 5: Spot welding pure nickel tabs at the tab positions of the positive tabs cut in step 4, and soften the tabs welded with pure nickel tabs to obtain finished positive tabs;

[0039] Step 6: Weigh the negative electrode hydrogen storage alloy powder, conductive agent, dispersant, and binder required for the negative electrode of the nickel-hydrogen battery to prepare the negative electrode slurry, and coat the negative electrode slurry on the punched nickel-plated steel strip, which is conductive The agent is carbon black powder, and the binder is CMC;

[0040] Step 7: Transport the nickel-plated steel strip coated with the negative electrode slurry in step 6 to the drying box for drying;

[0041] Step 8: Rolling and slicing the dried nickel-plated steel strip produced in Step 7 into a finished negative electrode sheet;

[0042] Step 9: Use a winding machine to wind the finished positive sheet and separator prepared in step 5, and the finished negative sheet prepared in step 8 into a cylindrical shape, and put them into a nickel-plated steel case, where the separator is set on the finished positive sheet Between the genuine negative electrode sheet, the pure nickel belt tab of the finished positive electrode sheet is at the open end of the nickel-plated steel shell, and the diaphragm is one of PE, PP or nylon;

[0043] Step 10: Roll groove the open end of the nickel-plated steel shell in Step 9, and spot weld the prepared battery cap to the open end of the nickel-plated steel shell;

[0044] Step 11: Fill the nickel-plated steel shell with electrolyte in Step 10, and seal the open end of the nickel-plated steel shell containing the electrolyte to finally produce a nickel-hydrogen battery, where the electrolyte is one of KOH solution or NaOH solution .

[0045] The anode of the nickel-hydrogen battery provided by the present invention contains spherical Ni(OH) 2 , Cobalt coated spherical Ni(OH) 2 , CoO powder, binder, using this nickel-hydrogen battery positive electrode to make the nickel-hydrogen battery has the advantages of good low-temperature discharge performance and high discharge efficiency.

[0046] Such as figure 1 As shown, 35%-60% Zn3 spherical nickel hydroxide (KL4#), 35%~62% cobalt-coated spherical Ni(OH) produced in Kelong, Henan 2 , 2.5% to 6% of conductive additive CoO powder and 0.5% to 1.0% of binder PT powder, the total mass percentage of the above components is 100%, according to the above proportions, dry configuration and mix uniformly as a low temperature positive electrode The formula is compared with the common formula of common spherical nickel hydroxide as the positive electrode, and the nickel-metal hydride batteries of the two positive electrode formulas are charged at 0.1C for 16h at a low temperature of minus 40℃, left for 30min, and then discharged at 0.2C to 0.9 The discharge effect is compared under the same test condition of V. figure 1 It is known that the discharge efficiency of the nickel-hydrogen battery with the normal positive formula is 72% and the median discharge voltage is 1.01V, but the discharge efficiency of the nickel-hydrogen battery with the positive formula of the present invention is 92%, and the median discharge voltage is 1.12V, so this The discharge efficiency of the nickel-hydrogen battery with the positive electrode formula of the invention is significantly higher than that of the ordinary nickel-hydrogen battery under low temperature conditions.

[0047] The performance parameters of the ordinary nickel-hydrogen battery and the nickel-hydrogen battery of the present invention are compared, as shown in Table 1.

[0048]

[0049]

[0050] Table 1

[0051] It can be obtained from Table 1: The internal resistance of the nickel-metal hydride battery of the present invention is less than the internal resistance of ordinary nickel-metal hydride batteries. Because the internal resistance of the battery is large, a large amount of Joule heat will be generated and the temperature of the battery will rise, resulting in a decrease in the battery discharge working voltage and a shortened discharge time. It has a serious impact on battery performance, life, etc.; at the same time, the nickel-hydrogen battery and ordinary nickel-hydrogen battery of the present invention are discharged at a 0.2C discharge platform at a normal temperature of 25°C, a 1C discharge platform at a normal temperature of 25°C, and a 0.2C discharge at a low temperature of -40°C. The platform is tested, and the results show that the platform voltage of the nickel-hydrogen battery of the present invention is higher than that of an ordinary nickel-hydrogen battery, that is, the performance of the nickel-hydrogen battery of the present invention is higher than that of an ordinary nickel-hydrogen battery; the charge retention rate of the nickel-hydrogen battery of the present invention is also obvious Higher than ordinary Ni-MH batteries.

[0052] Example 1:

[0053] Weigh the components of the positive electrode according to the mass percentage, 35% spherical Ni(OH) 2 , 62% cobalt-coated spherical Ni(OH) 2 , 2.5% CoO powder, 0.5% binder, the total mass percentage of the above components is 100%, and the weighed CoO powder is passed through a 100-mesh sieve for use. Manually stir until the CoO powder and the binder are not visible to the naked eye It can be seen that after adding it to the powder mixer, the powder mixing time is 3h, the mixed positive electrode powder is filled into the foamed nickel matrix with the printed tab position, rolled into a sheet, and the roll is pressed into a sheet of hair The soaked nickel substrate is cut into positive plates, and then spot-welded pure nickel with tabs at the tab positions of the cut positive tabs, and the positive tabs welded with pure nickel tabs are softened to obtain finished positive tabs;

[0054] Weigh the negative electrode hydrogen storage alloy, the conductive agent carbon black powder, the dispersant, and the binder CMC required for the negative electrode of the nickel-hydrogen battery to prepare the negative electrode slurry. The negative electrode slurry is coated on the punched nickel-plated steel strip and dried. Rolling and slicing to make finished negative sheet;

[0055] Put the prepared positive electrode sheet, separator PE, and finished negative electrode sheet into the coiled steel shell with a winding machine, then roll groove, spot welding battery caps, fill electrolyte KOH, and seal, and finally produce nickel Hydrogen battery.

[0056] Example 2:

[0057] Weigh the components of the positive electrode according to the mass percentage, 60% of spherical Ni(OH) 2 , 35% cobalt-coated spherical Ni(OH) 2 , 4% CoO powder, 1% binder, the total mass percentage of the above components is 100%, and the weighed CoO powder is passed through a 100-mesh sieve for use. Manually stir until the CoO powder and the binder are not visible to the naked eye It can be seen that after adding it to the powder mixer, the powder mixing time is 2h, the mixed positive electrode powder is filled into the foamed nickel matrix with the printed tab position, and the roll is pressed into a sheet, and the roll is pressed into a sheet of hair The soaked nickel substrate is cut into positive plates, and then spot-welded pure nickel with tabs at the tab positions of the cut positive tabs, and the positive tabs welded with pure nickel tabs are softened to obtain finished positive tabs;

[0058] Weigh the negative electrode hydrogen storage alloy, conductive agent, dispersant, and binder required for the negative electrode of the nickel-hydrogen battery to prepare the negative electrode slurry. The negative electrode slurry is coated on the punched nickel-plated steel belt, dried, rolled, and sliced Make a finished negative sheet;

[0059] Use a winding machine to put the prepared positive electrode sheet, separator PP and finished negative electrode sheet into the coiled steel shell, and then roll the groove, spot welding the battery cap, fill the electrolyte NaOH, and seal, and finally produce nickel Hydrogen battery.