Electroplating process of nickel-plated steel strip for battery

Abstract

The invention provides an electroplating process of a nickel-plated steel strip for a battery. A base strip is subjected to unwinding, pickling, electroplating, water washing and rewinding to be produced into the nickel-plated steel strip. The pickling step specifically includes the steps that the base strip is placed in a pickling solution for 0.5-1.0 min with a certain traveling speed, the pickling solution is prepared form hydrochloric acid, sulfuric acid and water, the mass concentration of chloride ions in the pickling solution is controlled to be 4.2-5.0g/L, and the pH value of the pickling solution is controlled to be 0.1-1.0. The electroplating process of the nickel-plated steel strip for the battery is simple and feasible, the steps are simplified, the yield of good products of the steel strip is increased, and the waste water treatment cost and the electroplating solution management and control cost can be reduced.

Description

technical field [0001] The invention relates to an electroplating process for a nickel-plated steel strip for batteries. Background technique [0002] In the prior art, the nickel-plated steel strip is generally made by unwinding the base strip—pickling—washing—electroplating—washing—rewinding. The pickling solution is sulfuric acid with a concentration of 120-150g / L and The mixed solution of rhodin with a concentration of 0.3-0.5g / L is mainly due to the bias of technicians, who think that hydrochloric acid is highly volatile, and after bringing chloride ions into the electroplating solution, along with the chlorine The increase of ion concentration will produce toxic chlorine gas during the electroplating process, which will cause great damage to the respiratory tract of employees and does not meet the existing occupational safety requirements. In the prior art, the baseband must go through a water washing process before electroplating after pickling. The purpose of water ...

AI Technical Summary

Problems solved by technology

In the prior art, the baseband must go through a water washing process before electroplating after pickling. The purpose of water washing is mainly to wash off the residual acid on the baseband and avoid the influence of pH on the current efficiency of electroplating. This is mainly because nickel plating The pH of the electroplating solution has a significant impact on the current efficiency. Generally, the electroplating current efficiency is close to 99% when the pH value is between 4 and 6. When it is lower than this range, the current efficiency will be significantly reduced. The increase of the concentration of nickel ions will cause the composition of the plating solution to be readjusted, which will waste electricity, labor and other problems. Therefore, there will be a washing process between pickling and electroplating to prevent the pickling solution from being brought into the plating tank.

However, the water washing process will oxidize the surface of the substrate after rust removal, that is, pickling, resulting in poor bonding between the electroplating layer and the substrate after the material is electroplated, and bulges are prone to occur; moreover, the washing solution needs to be replaced frequently. The washing solution can only enter the wastewater system, and the company needs to spend more on wastewater treatment; in addition, the washing process will increase the winding times and running strokes of the substrate, which not only leads to a low utilization rate of the substrate in the electroplating process, but also increases It is difficult to control the parallelism of winding, which increases the process loss of steel strip production, and the products are prone to problems such as uneven winding, ruffles, S-shaped, bulging, etc.

In addition, because the electroplating solution will be carried out during the electroplating process, it is necessary to add nickel chloride during the production process. In this process, the first thing to do is to regularly detect the composition of the electroplating solution, and then according to the inspection results. The composition of the electroplating solution is adjusted, the operation is more complicated, and the cost of electroplating solution control is relatively high