On Monday, March 2, 2015 at 9:53:26 AM UTC-8, Tim R wrote:

We have an old Mac laptop with a missing charger.

I thought maybe I could remove the battery and charge it directly. There is not just + and GND on that battery, there are a lot of terminals and apparently a processor.

Yeah, the battery and charge circuitry is smart, which means it's a mess to
tamper with. The 'missing charger', on the other hand, is just a voltage source,
you can get replacements cheap, compared to a battery replacement price.