Lithium Batteries: Any Suggestions?

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dpalm
Cucciolo - the Lil Pup
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Joined: Mon Aug 12, 2013 12:56 pm

Lithium Batteries: Any Suggestions?

Post by dpalm » Fri Sep 25, 2015 4:11 pm

I have a 1975 Ducati 860 GT, which I bought from ProItalia in Glendale in 1982 and have used to commute and cross the country several times. It had been modified when I got it to twin front discs, Contis, etc., and the triangular side panels were removed and the tank and fenders painted a desert khaki with white stripes, which is surprisingly attractive.

Anyway, I am wondering about replacing the traditional battery with a compact Lithium battery which could be mounted out of sight (suspended from the plastic tray?), thereby freeing up the area behind the rear cylinder. The bike is a kick start, so the battery does not have to do a lot.

Also, the bike cooks lead acid batteries, especially during long rides. I hope a lithium battery will last longer (the longest I have had one battery is 2 years, and this required re-filling the cells frequently).

On the other hand, I understand that lithium batteries are sensitive to overcharging (Shorai warns against anything over 15.2V, which I doubt the bike generates, but I will have to check). I have a notion that lithium batteries have their own circuitry to prevent overcharging -- am I mistaken? (The Shorai website does not provide much information on this.) If the battery does not have its own regulator circuit, has anyone tried rigging one?

Any advice is appreciated. Thanks.

Duncan Palmatier

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Craig in France
Cagiva Indiana
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Location: Montpellier, France

Re: Lithium Batteries: Any Suggestions?

Post by Craig in France » Fri Sep 25, 2015 11:52 pm

Hi Duncan,

Before you go too far down this route, you really should check out your charging system. There's simply no way you should be destroying batteries in 2 years - the battery I currently have on my bike is approaching 10 years now. If you're losing fluid, you're over-charging, i.e. your reg/rec isn't working correctly. And, as you seem to appreciate, over-charging will fry a Lithium battery even more quickly than a lead-acid. Have you stuck a meter across the battery with the bike running, and at various rpm?

You might also look at getting an AGM battery. They're not as small as lithiums, but they too can be installed whichever way you want. As you say, with a kick start bike, you don't need anything large (either physically, or in terms of electrical storage capacity). You're only really looking at something that can provide a bit of reserve for running with full lights on while riding at low revs.

That said, just be aware that it wasn't unusual for manufacturers at the time to use a large battery as an aid to controlling the output from the alternator. For example, fire up a Scrambler with the battery out, and you immediately toast the reg/rec. Early Laverda 1000s even came with just a rectifier, the battery being left to do its own 'regulating'. (An idea that didn't work so well, it should be said ....)

But yet another reason for making sure the reg/rec is working properly.

HTH

Craig

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abmartin
SSD900 Darmah
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Joined: Tue Apr 10, 2007 4:08 pm
Location: New Brunswick, Canada

Re: Lithium Batteries: Any Suggestions?

Post by abmartin » Sun Sep 27, 2015 3:14 pm

Your regulator is most likely shot. This is a common problem with these bikes. The good news is that replacements are easy to find and relatively inexpensive.

Bruce
1979 900SS
Fredericton, NB
Canada

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