Gel batteries

Gel cell

— one subtype of lead-acid batteries has an electrolyte that is not liquid but thickened to a gel-like state. This design offers several advantages over the classic version (see above): a greater number of charge-discharge cycles (and thus a longer service life); minimal electrolyte and accompanying gas leakage; no maintenance required (see "Maintenance"); resistance to deep discharges and temperature fluctuations, among others. On the other hand, GEL batteries are significantly more expensive.