Purchased a solar-powered golf cart. It's great except the batteries really don't get charged when the cart is out in the sun. The batteries are 8v Trojans FLA and it is a 48v system. There is a solar panel roof which has a placard that says SPSM- 230D underneath. I googled that designation and it seems to be some type of Made in China system that doesn't have a good name. What can I do to improve things and get the system running properly? Please speak to me like you would speak to a three year old. I have no electrical aptitude.