[echo-francis]

update: my car is now (lead acid free) my new battery is a lifepo4 20ah battery in parallel with a 108farad 16v capacitor ( 6 650farad 2.7v capacitor in series) it weight about 12 lbs.






the capacitor are there for the cranking amps because my lifepo4 battery can't start the car alone but the capacitor alone can do it . another use of the capacitor will be when I have to reinstall my belt (I dont want to charge the lifeo4 battery with my alt).

I found 2 li ion drill batteries and I thought: how can I use the power of those batteries to go further without belt. the solution, use the electricity of those battery to power my electric water pump. I made a switch that chose the source of the ewp (main battery or drill battery)
the battery is made of 20 3.7v 1.4ah li ion battery (5 packs of 4 battery in series in parrallel) that give a 7ah 14.4v battery