Battery defective after 5 months. Seller responded immediately and sent a new battery free of charge. The old one didn't have to be returned either, so no additional costs.
We decided on this supplier or replacement battery with a second attempt and are absolutely satisfied. Simply remove the old battery and install the new one and it works. No driver upload or anything like that was necessary, which is sometimes necessary with some other replacement batteries.
The battery lasts a very long time. So far no problems.