smokinjoe73

So I got my battery from the Netherlands (off ebay). It was $45 to my door. Looks awesome. I plan to mount it under the seat as a never get stuck with a dead battery plan.

It is super compact & light & I plan to get another one for my racebikes. Figure I can swap it to whichever bike I am racing and save a ton of weight.

Now I just have to figure out how often & how to charge it. It seems to have 13.7 volts as it sits.

98VTRrider

Wow, $45 shipped from Netherlands is impressive.

For occasional charging could you just make a jumper to run it parallel with the main battery? Then it would charge on your ride, just have to remember to unplug it when you get to work.

E.Marquez

Just ordered one for myself ... will have a look at the cells when it gets here. Planning on using it as a primary battery on the 990 SM

macdee

hi joe would you have a link for this battery
thanks

smokinjoe73

Here is the link bruthaman 8 Cell A123 18650 Motorcycle Start Battery 13 2V2 2AH 12V New A123 Battery Pack | eBay

Just ordered a second one for racing.

7moore7

Crap that's cheap. I'd do what 98VTRrider suggested- wire it in every couple of months to charge it. I can vouch that if they are healthy cells they will sit for a long time and hold charge.

macdee

thanks joe
just might have to get one of those

sjscicluna

Wire it in parallel with a relay and an override switch so when the bike is running its charging and when you turn the bike off it disconnects the connection the override switch will allow jump starts.

smokinjoe73

sj, I was actually thinking of putting a battery disconnect switch on the backup battery for now. This way can turn it on when I need it.

The question is, if the Li battery is only used in emergencies, how often do I really need to charge it? I was under the belief that they will sit a long time without maintinence.

7moore7

Yeah I think every other month or so would be on the safe side. I have a pack that's 1 year old still holding a charge... and I didn't treat that pack well at all either. But it was also stored in a cool dry place. It will be interesting to see how they do romping through pothole land in sub-freezing temps... but I'm a huge fan of the LiFePO technology and would trust it myself.

RoadManiac

Lithium battery are horrible in cold weather
because when cold it just wil not conduct as warm so starting up will take up to 4 try's and looking quite stupid when it doesnt start then you scare the **** out of those who are watching(or not) with a huge backfire
i take it out everynight..... made easy by R/C gold connectors and velcrostrip

E.Marquez

No need to go through that, just turn on the power and headlight for a min or so.. same thing Helo pilots do in cold weather .. pull some juice for a min and then start.

E.Marquez

Uggg, still waiting on mine, going on 4 weeks now....

RoadManiac

thanks for the tip

carkifelek

joe, $45 for a lithium battery, that too from Netherlands, I must say I’m surprised. I read your query about how to charge it, please do not connect it in parallel with the main battery. You can use only one battery at a time. Since your current battery and this one will have a voltage difference, they won’t be able to provide the required current, (up to 30A) at the time when engine is being started. You’ll have to charge the battery outside to be safe.

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