I have been in this business since 1983. Over the years I have seen many gadget devices to come along "claiming" they will rejuvenate and de-sulphate your lift truck batteries. Trust me, THEY DO NOT WORK. The ONLY thing that will work is PROPER maintenance, watering, and cycling. I have seen batteries that were properly maintained survive for 15 and 16 years and still be at 80% capacity, DO NOT use fast chargers!!!! They will literally cook a battery! Fast chargers reduce the costly expense of a battery from a mfg. life expectancy of 8 years to 18 months!!!