Battery type for permanent magnet alternator?

[AgentX]

Hello wise ones-

I'm pretty sure I read I should not use a Li-ion battery with my permanent magnet alternator due to the reality of over-charging. Is this correct?

And if so, what's the next best bet for a small battery to use with a Lucas-style alternator setup? Just a small sealed lead/acid type? They look cheap and can be small (my needs are not great, 5-7ah, kickstart-only single cylinder) but are heavy.

 

[cleoncleon]

You could consider a Sparx Capacitor.
Running one on a XS650 PMA charging system I pieced together from Banshee parts..
Works well, no headlight flicker.

 

[Tim]

I'd think the regulator/rectifier would be the real issue with a li-iron battery (they're not li-ion if you're using a Ballistic/Shorai etc.).

Haven't heard anyone with problems running one with a PMA. But as was mentioned, the PMA provides enough juice to start the motor, which is all your battery really should be used for anyhow. Aside from starting the motor, the only time it gets used is to provide a bit of juice to keep lights bright when the engine is idling, but the PMA produces enough voltage at idle to do this work. You don't need a battery.

 

[AgentX]

I am running a Boyer Powerbox which is a battery eliminator reg/rect, and it works in a pinch for a blown fuse, but the lights flicker and it dies at idle unless I crank it up pretty high at the throttle stop. I only want a battery to smooth things out in those type of situations. It's really not much of a drawback, and everyone I know on the Enfield board who's tried a battery eliminator has gone to backing it up with a battery, except one guy who's running a Hunt magneto for his ignition and powering the lighting off the AC alternator. Sounds like a cool setup, but 1) mags are hugely expensive and 2) if you're running an alternator anyhow, as for the lighting on a street bike, I don't quite see the big advantage of the mag.

I replaced my alternator with the newest electric-start model from Enfield, so there's no other way to get more power out of it that I know of. Not having any parasitic draw or anything, either.

I installed an HID headlight and I don't think the flickering is particularly good for the lamp, and since on/off with HID is the big power draw, a battery is the best thing for me right now.


Part of the problem is riding in India, especially at night: the low-RPM/stop-go nature of traffic and road surfaces doesn't let the alternator put out a ton of power much of the time.