thedarlington
100 W
this info is out there and spread out all over, so here's a dedicated "BMS free zone"thread specifically for this, when starting out BMS can easily be the biggest pain to understand, most don't even have a brand and each have obscure specs making them hard to compare, and then many very easily fail, often the most frequent failure point to a non working ebike. Its easily the shadiest part to ebikes with little details and then trying to compare them... so instead here's a thread to those of us who preffer a more purist simpler solution, yes you do need to watch #'s a bit more closely but it's also more rewarding to know exactly whats going on with your ebike, sorta like manual vs automatic.
rule of thumb>>> [#Series * Voltage] & [#Parallel * mil AMP hours] = total Battery Volt & mAmphrs ... LIFEPO4 @ 3.3v, & LIPO @ 3.7v
some options for you are:
LIPO - - simple and robust batteries, small and lightweight battery packs which are not as delicate voltagewise as lifepo4, many cheap low voltage alarms ($1) set to go, but more expensive and dont last as long, works out to about double lifepo4 cost? (citation needed) manual balancing (is it needed for lipo?)
CELL LOG Method - - for LIFEPO4 & LIPO designed to watch many connected batteries at the same time, can add a low voltage alarm, connect individual cells by series of 8, manual balancing (or main charge and then manual balance w/ battery medic overnight?)
INDIVIDUAL voltage alarms and low voltage monitors LVMs, these are cheap on ebay ($1-2) but mostly for 3.7v lipo's, so cheap for a visible digital readout, and come with buzzer already, if i could find some for lifepo4 id be in BMS free heaven, also need manual balance (battery medic?), or perhaps mod them down to 3.3v, the digital readout will work, its only the alarm part that needs modding
feel free to add your own info or correct my stuff
rule of thumb>>> [#Series * Voltage] & [#Parallel * mil AMP hours] = total Battery Volt & mAmphrs ... LIFEPO4 @ 3.3v, & LIPO @ 3.7v
some options for you are:
LIPO - - simple and robust batteries, small and lightweight battery packs which are not as delicate voltagewise as lifepo4, many cheap low voltage alarms ($1) set to go, but more expensive and dont last as long, works out to about double lifepo4 cost? (citation needed) manual balancing (is it needed for lipo?)
CELL LOG Method - - for LIFEPO4 & LIPO designed to watch many connected batteries at the same time, can add a low voltage alarm, connect individual cells by series of 8, manual balancing (or main charge and then manual balance w/ battery medic overnight?)
INDIVIDUAL voltage alarms and low voltage monitors LVMs, these are cheap on ebay ($1-2) but mostly for 3.7v lipo's, so cheap for a visible digital readout, and come with buzzer already, if i could find some for lifepo4 id be in BMS free heaven, also need manual balance (battery medic?), or perhaps mod them down to 3.3v, the digital readout will work, its only the alarm part that needs modding
feel free to add your own info or correct my stuff