Yes, thermal design is key to this working.. the sensor has to be coupled to the cells (mostly) and not so much to the outside world.
It's not entirely a circuitry problem- it turns out that the mV-level cell voltage depression just does not happen at all if the current is too low, and also cells (depending on charge history) may exhibit false depressions that will cause premature termination of charge.
The time constants are long, so other techniques can be used to reduce the effect of noise (or interaction from other chargers) but there are other effects.
Best regards, Spehro Pefhany