The USB rechargeable packs used by beam emitters give 55 to 60 hours and recharge in about two hours. The habit worth building is charging at the end of an event rather than the start of the next one, because that is the day you discover a pack has failed rather than the day you need it.
Cold weather draws batteries down faster. Winter events - snowmobile and ice racing especially - should plan on extra charge cycles and a warm place to keep spares.
The eight-bay desktop charger gives the same charging power to one pack or eight, with no trickle overcharge damage, so packs can live in it between events.
The hand controller battery runs about 140 hours per charge and takes two hours to recharge.