Replacement Battery Not Recognised/Charging

Not a new question particularly - got a replacement battery from here only for the BIOS to tell me it's unrecognised (not OEM) and won't be charged. Tried this to no avail. Also flashed with the latest BIOS from Dell...

Removed the CMOS battery temporarily, can't get it to charge - LED remains flashing alternately white/amber.

I'm running ubuntu, not windows... any ideas gratefully received.