A sealed, low maintenance battery (10, 100) is formed of a casing (14, 102) having a sealed lid (12, 104) enclosing cell compartments (22, 110) formed by walls (24, 132). The cells comprise a stack (26) of horizontally disposed negative active plates (30) and positive active plates (28) interspersed...http://www.google.co.uk/patents/US4603093?utm_source=gb-gplus-sharePatent US4603093 - Lead-acid battery
