Stainless steel battery contact to Hasal finish pcb 2

[rossieinexile]

I curently have a sub assembley that uses a stainless steel battery contact which makes a kiss connection with a pab on a hasal finish pcb. After a period of 3 to 4 weeks there is evidence of corosion of the pad which is causing the unit not to power up.

My questions are

(1) Has any one ever used stainless steel as a battery contact.?
(2) Is hasal a suitible finish for a fixed kiss connection
for a battery contact. ( 4.5 volts)

(3) if i changed the battery contacts to nicol plated stainless steel and touched up the hasal with solder would this be a plausable rework?

 

[felixc]

HASL isn't made at all for use as a connector surface. It is tin/lead. The only thing it can mate to is another tin/lead contact. Otherwise, it will develop "fretting corrosion", that is a thin layer of tin/lead being transferred to the steel contact with the rubbing action, and then this tin/lead deposit that oxidises and becomes non-conductive. The same type of problems happen what people mate connectors where one part is a tin/lead version and the other part is a gold-plated version. No good! All tin/lead, or all gold (or other non-oxidizing material).
In your case, you may want to get these PCB contacts gold-plated. It can be a pain, but it can be done, using the kits made to repair goldfingers.

How many amps go through the contacts?