Lithium Ion Batteries

All to do with wiring, charging or just trying to figure out whats gone wrong.

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Lithium Ion Batteries

Post by texranger »


Well, some of you may remember me from a few weeks ago when troubleshooting a no-charge issue on my GT550A. After having fixed that, I took the bike for a nice, long ride on Sunday. Almost 150 miles of fun and visits to gas stations (getting only about 17 miles to the gallon but that's for another topic).

I fully charged the battery the day before my ride but a few miles from getting home she completely died. Pulled over, kicked it a few times and nothing. Waited a few minutes, kicked it again and she started only to die again 30 seconds later. Checked all the connections and everything looked OK. Called the wifey and asked her to bring me a battery. Got home and first thing I did without shutting her off was to check if she was charging...and she was.

Additional details: the battery that was on the GT is a Lithium Ion type. The battery I put to get me home is an AGM type.

So, here's my question: could it be that these old charging systems don't do well recharging these modern Lithium Ion batteries? I have heard some mixed opinions on them regarding not lasting long.

Maybe it's due to a weak voltage regulator? Any thoughts and feedback will be appreciated!
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Re: Lithium Ion Batteries

Post by Flouxes27 »

Hey there. Wonder if you learned anything new since this post? My understanding is you CAN use Lithium-ion's, but you optimize it by getting a new regulator-rectifier (reg-rec) and test the output of the reg-rec making sure it isn't exceeding the batteries charging max (Lithiums have a tendency to combust when over charged). The best info I have obtained, so far, is that AGM's work the best on these old vintage bikes as a short answer. I bought a Shorai LiFe for mine and a new reg-rec from somewhere in UK, but I haven't gotten to that point in my build yet to test it out.
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Alan H
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Re: Lithium Ion Batteries

Post by Alan H »

AGMs on triples work ok if the rest of the wiring is good. Not tried lipos but they are a different beast altogether and don't like being over/fast charged/discharged (by electric starts!) or they get hot and die quicksticks. OK on my model helicopters, mind!!
AGMs don't like to go below 9v or so and will die then, so either turn the ignition off when not used, or better, disconnect the battery after the last run before the winter hibernation.
A good earth system and a good connection from battery to regulator is what's needed. No need for a solid state reg/rec, the original system is fine if looked after.
I've used a few AGMs on several current 550s and Hippo and they spin the engine over much better, but I daisy chain an earth from battery- to everything under the left side panel and make sure I have as near as dammit battery + voltage at the (standard) regulator.
Anything other than a lead acid battery is a waste of money on a bike without an electric start though.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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Re: Lithium Ion Batteries

Post by tz375 »

I use a small AGM battery on the Phat Trakka and now it has an electric starter, I was surprised how well it spun the motor over. It uses a solid state Reg/Rectifier and until I managed to short a fuse, it charged perfectly well and always stayed within limits. Replaced the fuse and things are back to normal.

With Lithium chemistry, voltage control is more critical and if you let the battery completely discharge, there is no walking t back from death. MOSFET would be a good way to go with a permanent magnet system but I don't know if they are even available for our electromagnet systems.

I found the key to a healthy charging system is a solid battery voltage sense for the regulator. It's easy to splice in a new sense wire to get the actual battery voltage. On a stock system, the sense wire tends to carry a lower voltage and that leads to boiled batteries.
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