superdenso

Two years ago I had a dead battery in my LS. The battery was jumped, I drove home (45min) and the battery was not reliable. The Lexus 84mos battery was replaced with an Optima Yellow Top 34/78. The Lexus battery sat in a corner in my garage for two years until I tested it last weekend and it barely showed any volts (never saw that before). I connected a charger to it for the weekend. After charging the battery for 2 days the charger indicated 100% power and switched to maintain mode. The battery was put into an Acura and driven around for 5 miles. The Acura was parked outside for 48hours and the temps dropped to 43deg. at nite. This morning the remote start engaged the starter and the engine twisted to life again. I consulted Optima about this, and they said crystals can form inside the battery and prevent it from operating efficiently. The charger modulated the amps and volts for 2 days and the battery works again. It was suggested by Optima that a battery be "maintained" by a charger on some interval. From this experience, I will let the Optima 400 condition my batteries once a month.

Parts:
Optima 400 charger
Lexus 84 month battery (severely discharged)