Lithium Motorcycle Batteries

[Cambridge K]

The Lithium Iron Phosphate battery is the ultimate in weight versus power technology. This battery weighs in at only 2.12 pounds and offers an incredible 270 C.C.A. This is a drop in replacement for your Lead-acid battery, and will require no change to your stock charging system.
Has anyone used or tried these out?
http://www.batterystuff.com/batterie...18A1-BS12.html
http://www.shoraipower.com/default.aspx
I can shed 10 lbs off my bike !

[FireboltEric_MA]

I have one. love it. no complaints at all.

[OreoGaborio]

I just picked up a 4 cell A123 battery pack... It might be a little weak for the SV, especially if the cells are cold, but considering the price and weight I couldn't pass it up.

(70 bucks shipped and just .8 lbs)
http://www.build-stuff.com/x-cell.htm

[typeone]

this is a topic over on AF1 too, some additional info about lithium batteries and Shorai...

Hi,

I can answer some of your questions and you can visit the site...http://www.antigravitybatteries.com/ for more in depth info.

The lithium battery won't really help a lot if your bike doesn't start well in the first place.. but what it does offer if a little bit quicker turn over rate because of higher Cold Cranking Amps, but there are differences in the lithium Lifepo4 batteries like the Shorai Company in your post....

There are two different types of Lithium Lifepo4 Cells... Prismatic and Cylindric... being blunt the A123 Cylindric cell is the only tried and trusted unit that has major cranking amps. A123 systems is the real originator of the lifepo4 chemical makeup that is the industry standard. There are many Chinese knock offs in the Cylindric style, but nothing comes close to the peak amp output or constant amp rate, so no one uses them. The Shorai in your picture is made of Prismatic Cells... Prismatic cells do offer higher Amp Hours, but much lower cranking amps than Cylinderic. They do offer the weight saving though. I like their case alot and the price is very good. But they are not close in power relatively speaking to a battery made of A123 cells....But then again if they used premium cells the batteries would be more expensive. For example their 7 amp hour battery puts out 107 CCA... a comprable 7 amp hour battery using A123 cells (like our Antigravity 4600) puts out 240 Cold cranking amps twice as much... and that will actually spin your motor faster. I actually use the 4-cell in my SXV 550 which is 2.3 amp hours and puts out 120 CCA... So there are trade offs in price performance and looks... just do some research first.

If you have any questions let me know. I'll answer them honestly.

[Yknot]

Nice find Pete, ordered one myself. You total loss on the SV?

[OreoGaborio]

Not total loss. If I were I'd go 8 cell.
4 cell is cutting it close as it is. I've heard mixxed reviews on the 4 cell w/ SV's.

[FireboltEric_MA]

Hmmm...My 4 cell ran my street bike without a problem. Lights on full blast and all. I would think a track bike would be good to go no-problemo.

I've had the battery only one season, so that is all I have for experience with them....

[OreoGaborio]

I4 though, right?

The SV's a twin so that's the only concern. Half the number of cylinders but they're twice the size. Requires a little more cranking power than an I4 so the SV guys have had mixxed results.

I'm sure I'll be alright in normal temps, but when the batteries are cold it'll be a little tougher. I've read, however, that once a load is placed on these batteries that they quickly begin to warm up.

We'll see what happens.

[Kurlon]

I thought the Lipo's needed high output chargers to charge correctly, didn't think they'd survive long on a bike's charging circuit?

[Garandman]

I'd like a lightweight battery for my WRX [car]. They don't seem to be available for that application?

[Yknot]

I am going to see how the 4 does with total loss on the Hawk. The only thing I need to run is ignition and if I start with a jump pack I would think it'd be good. Track days could be an issue so I'll keep a lead acid around. We'll see, I can always get another if it no work.

[OreoGaborio]

That's my line of thinking as well.

[Cambridge K]

Now I found more even lighter - a rider on another site told me about this battery - http://www.motowheels.com/italian/my...or=&collection
on a ZX-10R & his BMW with a quick disconnect between his 2 bikes.

[Kitt]

I didn't have a good experience with mine this year.

[ZX-12R]

I thought the Lipo's needed high output chargers to charge correctly, didn't think they'd survive long on a bike's charging circuit?

LiPo's have a slightly different chemistry than the LiFePO4 cells that are used in these batteries and have a different charge cycle as a result. I've quickly tried to find some information on the LiFePO4 charge cycle and what I've found suggest a charge cycle similar to LiPo which a motorcycle charging system simply cannot do.

LiFePO4 seems to be robust enough to tolerate the charge a motorcycle can provide and still operate properly but it would most likely perform better or last longer with a proper charge controller.

Better batteries could easily have the charge controller electronics integrated into them but the simple battery packs are at the mercy of charging system. At least with LiFePO4 you don't have to worry about your battery vaporizing should something go wrong.

[OreoGaborio]

Would a battery tender be of any help?

[Yknot]

I know they work slot better if the cells are balanced regularly. The one the I ordered doesn't have the taps for the cells. I know a engineer that specializes in battery technologies that I will be picking his brain about this. If he has any words of wisdom I will post.

[OreoGaborio]

I actually asked the seller of the one that I purchased about balancing the cells, since his batteries were advertised as having taps to do that, but here was his response.

balancing doesn't seem to be neccessary? I was the only manufacture using balancing taps and no one seemed to care. I finally removed them when I lowered the price. I've been running a 4 cell all summer that I intentionally damaged by over discharging. I ride around with four voltmeters and watch the cell behavior. At times they concern me a little bit, specifically one cell seems to charge up higher than the others but still within specs. It appears to be some sort of surface charge because as soon as a load is applied it falls inline with the others. A different cell drops off sooner at the low end but throughout the normal working range they seem to be self regulating. This explains why no one else worries about it. Despite being damaged, the battery performs flawlessly in my DR650.

You could probe the cell ends with a sharp pick if you're realy curious about voltages?

The most important thing is to not over discharge them. These batteries stay strong until the last crank, then die abruptly. They then rebound a little above the minimum voltage. Bump start the bike or get them on charge as soon as possible and your OK. As soon as you sense the drop off, don't continue to hold the starter button or you will damage the battery. Power tools have a special protection circuit but its hard to do with motorcycles because of the high cranking current.

As it turned out, the unit I received didn't have the load balancing taps anyway.

[ZX-12R]

Would a battery tender be of any help?

From what I have read, it looks like a true floating battery charger (like a battery tender) is OK since they will maintain a specific voltage within the safe range for LiFePO4 cells.

What troubles me is is there is no safety mechanism in the battery to prevent overcharging. Each cell has a maximum safe voltage of 4.2V. With a 4 cell pack, your max voltage would be 16.8V. Under normal operating conditions, the charging system on your bike will never get that high so in theory the battery should never be in a position where it could be overcharged. In real life there are lots of variables that dictate how much voltage the regulator in your bike provides with temperature being one of them. As your regulator gets hotter, its voltage increases. Under normal conditions this isn't an issue but if you have a marginal regulator to begin with, it could easily overcharge your battery. At least you don't have to worry about LiFeSO4 batteries exploding in this situation.

According to the rather limited datasheet, the recommended charge cycle for A123 LiFePO4 cells is a constant current of 3A until the battery reaches 3.6V where you then maintain a constant voltage of 3.6V for 45 minutes. For a 4 cell battery pack this would be 3A until the pack reaches 14.4V and then a constant 14.4V for 45 minutes. The current output of the charging system on a bike can vary wildly under normal operation and will never even remotely approach the recommended charging cycle. How this translates to long term battery performance is anyone's guess at this point. It could be a rather expensive loss if you find out quickly that your charging system isn't appropriate for the battery.

For total loss systems or racing applications I think they are a great idea and their benefits greatly outweigh their drawbacks. For street applications I'm not sold yet. They could work perfectly fine in one bike and possibly leave you stranded when you least expect it with another. Until there is proper charge management integrated with the battery, I'm sticking with tried and true AGM SLA batteries.