Out of curiosity will this give you more power? At the least shouldn’t it be lighter? Aren’t the lithium batteries lighter?
A dual bank of 4ea lead acid 155AH batteries have a useful AH rating of only 40% due to lead acid battery limitations. Instead of 48V at 155AH per bank, you only have about 62AH of usable capacity. Since you have two sets, that means you have about 124AH available from a full charge on a new set of batteries until you get to the point of needed a recharge. Since lead acid batteries get damaged easily with running them below 50% capacity, it's not uncommon for a 2 year old set to only have about 75% of their stated capacity available. That drops you down to 93 AH for total capacity. Not only that, but as a lead acid battery is depleted with use, the voltage drops, which decreases the power available at the wheels as you use it. Each one of those batteries weighs around 80#, so 640# or so of total weight in the cart for power.
A LiFEPO4 Lithium cell can delivery over 95% of it's stated capacity at the stated voltage. A 105AH cell can deliver over 100AH of actual usable power to the wheels at the full 52V rating. You get a slight bump in true voltage to the motor plus you get more available AH doing it. That's a single cell. The Polaris EVs I build get two 105AH cells, so you end up with more than 2x the range. On my personal EV I would get about 10-11 miles offroad on economy range and 2WD on a good complete charge with 18 month old lead acid batteries. With my dual 105AH setup, I could go 25-27 documented miles, with it in high speed/power and 4WD the whole time. Easily double the range while having more power and in 4WD the whole time.
Lithium can provide a higher surge current (inrush current needed for electric motors to spool up quickly) than lead acid, so yes, more power off the line or when you floor the pedal. On a Polaris with 8 large 12v batteries, you lose around 500# of dead weight so the suspension of the cart makes it ride over an inch higher without any changes other than weight loss. You gain agility, gain a lot of range, gain ground clearance, gain power/throttle response, gain top speed, gain payload capability (lost 500# of weight so now you can haul more corn), and can charge a dead bank to 100% in 5 hours instead of 12-24 hours. No topping off with water, no changing batteries every 2-3 years. What's the catch? It's not cheap. About $4250 for a single 105AH cell installed with all labor and taxes that would match the range of the OEM Polaris 48V setup. Add a second cell to double the range to over 20 miles offroad and it is about $7850 out the door. A lead acid set is about $2000 per 2-3 years in comparison and you get less power and more maintenance. If you're going to keep your cart, Lithium is the way to go. The difference in the cart is like going from a stock 1982 K10 with 175 HP to a built offroad K10 with 300HP, lift kit, and 35's.
