toxsickcity:
Anyways. I don't want to spend money on batteries and batteries would be 3 yr old or so.I just want to build the kit.
I understand that you don't want to spend money on batteries - which of us does?
However IMHO there is no simple fix that takes the form of building a kit.
If the batteries are 3 years old you may well be near the end of their lives. How many amp hrs have flowed in and out of the batteries during those 3 years?
If you re-wire your battery bands as @TomGeorge has suggested you may get a bit more life from them.
I get about 4 years from my lead-acid batteries with a lot of care.
...R