Not in this situation, I haven’t even taken a hearing aid apart yet, I’m a new user, and this info comes from building and repairing ebike batteries with nickel plated strips (that are as conductive as copper) this is why I’m suggesting trying it out on AAA batteries first. if problems occurs with copper wire first solder it to a small strip of nickel and spot weld the strip to the battery as we know that works and is something I have personally done. I did eventually buy myself a mini spotwelder for the bike batteries that is like this one.
I have noticed a trend towards these now though.
these are very cheap and may also do the job, but again I haven’t used one of these at all, let alone on a hearing aid.
On an additional note, most batteries with wire connectors on in my limited experience do not have copper wires they are a much harder stiffer material possibly steel coated with nickel.