Cordless lawnmower (Juniper Green EH14)

I have a Bosch Rotak cordless lawnmower available. The lawnmower is old but works fine as does the battery. The charger has stopped working. I have been unable to source a replacement. There seems to be a bit of rust on one of its pins. I am told that it might be possible to re solder the contacts but I’m afraid I don’t have that skill! So offering it to anyone who might or who could use the working parts.