In tail lights, it's hard to beat Cygolite Hotshots and Hotrods for value and brightness. They're reasonably priced, lightweight, very bright (but adjustable as needed), hold a charge well enough they don't need to be recharged every day (unless I'm riding several hours a day), recharge reasonably quickly, and the batteries are good for many charging cycles.
I have some battery powered taillights but those are relegated to my hybrid and errand bikes.
In headlights there are many suitable choices. For awhile I mostly used Light & Motion but I've mostly switched to NiteRiders, and I've noticed most of my local friends have as well. For serious nighttime riding it's hard to beat the NiteRider Lumina Dual 1800. Dual LEDs side by side, plus a properly designed lens to throw a well shaped beam that lights up the road rather than indiscriminately lighting up the trees and blinding oncoming traffic. It's pricey at around $150 or so, but really good for an all-in-one unit. And Outbound Lighting offers similarly good headlights with separate headlight/battery modules.