Using current measurments for smart charging a battery
There are a lot of methods used that make use of current information.  Coulomb counting, impedance tracking, and other methods.  Sometimes there's a battery gauge IC that works in conjunction with a charger to determine state of charge and when to terminate.

You can find a lot of information on this TI's website.  Maybe start here:

Battery Fuel (Gas) Gauge Overview 

Then poke around for more info on the various charger ICs.