... / SASO.SONCAP 4.long service minibus battery,truck battery,common dry charged battery:maintenance needed, dilute sulphuric acid needed. ... its useful life.Because the electric current can activate the chemical substances which in battery plate. And 30 minutes ... is enough to soak battery plate.Certification:ISO9001,ISO14001,ISO/TS16949,CE,SASO.SONCAP etc mini bus battery ...