How to handle the terminal acid climbing problem of VRLA battery

In the production process of lead-acid battery, it will encounter the problem of terminal acid climbing, and how to solve it？ The following summarizes some analysis and solution of terminal acid climbing problem.

Cause analysis and improvement measures of terminal acid climbing:

1. Status description

At present, there is a terminal acid climbing problem in VRLA battery, some will happen after a few months, some after a few years. Generally terminal acid climbing occurs in the negative terminal, because the negative terminal is Pb, PbSO4 is positive, PbSO4 is larger than Pb in molar volume, and smaller molecular gap. Pb has a large gap. Although lead and epoxy resin can be a very good combination, epoxy resin can seep into the surface layer of lead, but epoxy is not able to seep into the surface of copper, epoxy and Cu (we now use the terminals that is copper coated with silver) in combination with sealing is not so good, so acid climb along the pole and terminal surface, lead to terminal acid climbing phenomenon.

2. Cause analysis of terminal acid climbing:

2.1 Person: New employees are not skilled in operation, large employee turnover, less familiar operators

2.2.1 Object: Epoxy resin quality

Heating terminal equipment:

Cold weather can affect the binding force of epoxy resin and terminal. The device mainly uses heating the terminal and color epoxy groove of battery lid to increase the binding force of color epoxy and terminal, and also accelerate the circulation of epoxy.

Process temperature: 75 ± 5℃,

Method of operation:

First, add red Epoxy before the battery enter through the heating terminal equipment. The edge of the epoxy level is flush with the surface of the terminal hole.

Second, After dispensing the red epoxy, send it into the heating terminal equipment,and heating for no more than 1 minute.

Third, After it finish the heating process through the heating terminal equipment, quickly add the black epoxy, The edge of the epoxy level is flush with the surface of the terminal hole.

2.2.2 Battery lid structure: The lid does not have a epoxy guiding groove, epoxy can not seep into the bottom of the terminal, sealing is not good.

2.3 Method：

The terminals are improperly welded and too much tin is fused. As a result, the tin liquid or lead liquid blocks the epoxy guiding groove. The epoxy cannot seep into the bottom of the terminals, and the terminals and poles cannot be properly sealed.

3. Improvement measures for terminal acid climbing :

3.1 Change the structure of battery lid and add epoxy guiding groove design.

3.2 Choose the epoxy with good performance

3.3 When welding terminals, first use the soldering iron to melt a little tin and then use the soldering iron to melt the pole, add tin while melting, Do not add excess tin to only pursue full and beautiful solder joints.

3.4 Using the special designed welding terminal mould can effectively prevent the lead liquid or tin liquid from blocking the epoxy guiding groove when welding terminals.