Background info- My commute is ~20 miles with some good hills along the way. I charge my bike at work. My ebike is a DIY 24v 380w motor cyclone mid drive kit.
My 20Ah deep cycle SLA batteries finally kicked the bucket and I have some money for a much nicer battery. They did the job but just barely, with the system totally dead just before the end of the return trip(one extra, long steep hill finishes it off). The speed would noticably drop half way as well. I would like to have a lot more range.
I am looking into LiFep04 batteries- but im having trouble figuring out what I need and where to buy from. $600 is about the maximum I wish to spend, but I could go a little higher if it gets me a lot more power. Ping batteries has a 30Ah battery in my price range, but If I could get a 40Ah battery and assemble it myself I would prefer that. What would I need to build the Battery? I know I would need 8 40Ah cells and a charger. Do I need some sort of circuit to monitor the batteries? I am also having trouble finding a source that cells the Batteries, charger and circut all in one place.