{TAIL ~ at least one rechargeable cell} providing relatively efficient stored energy output at {HEAD ~ both relatively high and relatively low output current levels} 
{ TAIL ~ at least one rechargeable cell } providing relatively efficient stored energy output at { HEAD ~ both relatively high and relatively low output current levels }
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD