... up of positive and negative plates, special diaphragm, gel electrolyte, battery shell and security valve and so on ... be freely floating through the crannies of the gel, can be regenerated according to Pb-Ca alloy ... sealed up and maintenance free come true. The GEL battery series are specially designed for applying in ... 20°C to 25°C).Applied with German Gel formula, grid alloy and plate formula, the ...