On Wednesday, March 1, 2017 at 5:30:06 AM UTC-8, Roy Garden wrote:
At 11:58 01 March 2017, Jim White wrote:
At 10:29 01 March 2017, Roy Garden wrote:
You don't charge a LiPo from a lead acid charger.

Not strictly true Roy. According to the datasheet and user manual A12
batteries are compatible with a standard SLA charger however will
probabl
be optimum with a proper one. I use a Ctek Lithium XS for mine.

Absolutely, strictly, true.
You'll "Get away" with occasional charges from a lead acid battery charger

on LiFePo4 batteries (If the voltage is vaguely compatible)
But on a pack, you'll loose the "Balance" in the pack and in fairly short
order destroy the pack.

The differences between PB, LiPo and LiFePo4 are of the order of putting
Petrol into a diesel engine.
If you put the wrong stuff in the wrong place, You'll break things.

PB Chargers do not have such robust dead short protection as modern
chargers, and with LiPo can leave you open to causing a thermal runaway
on a LiPo.

Get modern chargers and batteries.

I'll agree with the sentiment to use Li chargers with Li batteries, however the comparison to petrol in a diesel engine is a bit far fetched. The LiFePo4 batteries that we should be using in gliders all have an on board BMS that balances the cells and prevents over and under charging. Any LA charger is current limited by design, even very old fero resonant versions. LiFePo4 batteries have to be heated to something like 600C to achieve anything like thermal runaway. On the other hand LiPo batteries are relatively easy to drive into thermal runaway, and that is the reason they should not be used in a glider.

Undercharging LFPs does shorten life expectancy, and most LA chargers are limited to 14V or so, which is likely to undercharge an LFP.