I killed Rakkman in The Fridge and opened the chest and found some shield called "The Bee", Jesus is this thing good. The capacity and recharge delay sucks but it has 28,000 AMP Damage and 0 Drain. I can take out bosses in 3 shots with my shotgun.
I'm gonna go back there once I'm level 50 and try over and over again until I can get a level 50 version of "The Bee".