Type:solar lamps Place of origin:Shandong China Port:Qingdao or Tianjin Payment ... -efficiency cell with service life ≥20 yearsStorage battery: valve-controlled sealed service-free colloid, silicon and lead-acid cells with service ... and over discharge, service life ≥5 yearsBattery box: molded, fully sealed to prevent water, excellent heat preserving performance, service life ≥20yearsService ...