Thinking of going LiFePO4

[hohisilver]

I have one of the cheap Chinese electric scooters which started appearing in this country a few years ago, but having now run it for nearly 2 years the original SLAs seem to be starting to "sag" a little. The cost of LiFePO4 seems to have been coming down and I'm beginning to think it will soon be time to take the plunge.

I've been looking at Headway cells and I like the way they seem to be easily assembled into packs, but I don't want to make a mistake on the BMS and charger front. I've started reading through the "old BMS" threads and what's been going on there looks very interesting. I'm running my scooter at 72V at the moment but (space permitting) I'll probably be looking at a 76.8V (24S) setup, just wondered if anyone has any advice on what I should be looking at charger-wise, and the availability/cost of your BMS Peter?

TIA

[retepsnikrep]

Well there are a lot of BMS out there. Make sure you review them. http://liionbms.com/php/bms_options.php

Ours is still a work in progress. Quite a bit has happened recently though We may have a 25 cell slave board or 2 x 16 cell slave boards and a master spare, price is around £50 for the blank pcbs. Parts are cheap enough say £150 off top of my head.

There is a lot of support on the BMS Thread to get you going. so if you have the ability to build the boards, read and absorb the threads and are willing to give it a go. Be our guest. Ask questions of others who are trying the system.

Re LIFEPO4 I would never go back any lesser battery. Once you have the lithium range and power you are spoilt for life

[hohisilver]

As a software engineer by trade and a sometime electronics hobbyist, you may be able to see why I'm interested I've done quite a bit of embedded software work over the years, sadly restricted to Windows programming these days. I did design and build a MIDI controller for my own use, using an Atmel AVR chip a few years ago though, on Veroboard .

So I'm not afraid to break out the soldering iron (although I hope there aren't any/too many surface mount chips!?). I've not done any PIC programming but having looked at your code samples it all looks pretty straightforward - guess I'd need a PIC dev board to do any reprogramming if I wanted to though?

Does that approximate parts cost include that neat display?

[retepsnikrep]

Does that approximate parts cost include that neat display?

Depends how much you can get one for on e-bay