Positive grid and preparation method thereof

Abstract

The invention discloses a positive grid and a preparation method thereof. The positive grid comprises following components in percentage by weight: 1.0 to 2.0% of Sn, 0.04 to 0.09% of Ca, 0.002 to 0.004% of Al, 0.001 to 0.004% of Ag, 0.02 to 0.04% of Na, and the balance being Pb. The positive grid has the advantages that Sn and oxides of Sn and lead are good conductors, the conductivity of contactlayer is improved; Ca can enhance the strength of lead, the compatibility between Ag and lead is good, the corrosion resistant performance of alloy is enhanced; Na can remove harmful substances suchas Cu, Sb, and the like in the alloy; the density of Al is low, Al is distributed on the upper layer of the alloy and protects other main components from being burned; a demoulding agent effectively strengthens the bonding force between the grid and lead paste; the grid defects are eliminated through high temperature age hardening, the grid strength is enhanced, at the same time, the grid grains are refined, the corrosion resistant performance and creep resistant performance are both strengthened, a battery prepared from the positive grid has the advantages of little internal resistance and long deep cycle life, and the capacity fade in the primary period is avoided.

Description

technical field [0001] The invention relates to the field of battery production technology, in particular to a positive electrode grid and a preparation method thereof. Background technique [0002] With the rapid development of electric bicycles, low-speed electric vehicles, electric sightseeing vehicles, electric sweepers and electric tools, the demand for power batteries is increasing, and the requirements for battery performance are also increasing. At the same time, as the country banned the production of cadmium-containing batteries and externally formed batteries, all power batteries have been adjusted to cadmium-free internally formed production processes in recent years. After the internally formed batteries were introduced to the market, it was found that the batteries were under high-current charging and discharging and deep cycle use. The phenomenon of initial capacity attenuation (that is, a sudden and sharp drop in capacity) is easy to occur, and the experience...

AI Technical Summary

Problems solved by technology

At the same time, as the country banned the production of cadmium-containing batteries and externally formed batteries, all power batteries have been adjusted to cadmium-free internally formed production processes in recent years. After the internally formed batteries were introduced to the market, it was found that the batteries were under high-current charging and discharging and deep cycle use. It is prone to the phenomenon of initial capacity attenuation (that is, the sudden and sharp drop in capacity), which will cause poor experience for consumers and bring huge losses to manufacturers

Through analysis, it is found that the battery with this phenomenon has a relatively large internal resistance, especially the internal resistance of the positive plate will suddenly increase in the late stage of discharge / charge, resulting in the battery not being able to discharge or charge.