The link I provided above is a charge controller I am using. It pulses
the output to 'detect' a battery (see if the voltage rises between
pulses). It also provides for a thermistor in the battery pack (the
ones I have utilise a Panasonic NTC, nominally 10k at 25C). On that
note, you should not try to charge a Li+ below about 0C or above 45C.

Li+ battery packs could have the charge controllers on board, but they
would be specials. Most packs come with the NTC and nothing else.

Cheers

PeteS