John is right to remind us of the safety issues.
i would contend that using a chip like the Maxim one is the best possible way to make a charger knowing it has a good reliable basis and a glance at the datasheet will show there's very little to go wrong.
Main message has to be don't charge damaged cells and don't try and restore or charge lithium-ion or li-poly with anything other than a charger designed for the task.
Neil