These Lithium-Ion Batteries contain no hazardous acid or heavy metals, so they're non-explosive and non-combustible. Non-spillable and maintenance-free, these have a 12-month shelf life before needing to be recharged. Capable of higher CCA's than lead-acid batteries and have a longer life; 1,000 cycles compared to lead-acid 300 cycles. 90% recharged by 100 current within 6 minutes.