Topic: Anyone using these tiny 12oz. lithium batteries? - Sold Out!

[kayaker43]

Batteries are all sold,.. I can't get any more at this price so they will be discontinued.......

I always raced with total loss ignition and a 5 AH battery. These new batteries are amazingly small and light. Here's a pic for comparison.



My next build will be for the street and I was searching for a magneto so I can dump the 8.9 lb battery and run some fake lights. The little X-Cell looks like a better solution, I can retain the charging system have full lights, electric start and still save 7.3 lbs!!

Those who want that naked racing look you can hide one of these tiny batteries anywhere.

For racing, one of these running total loss (they can be fast charged) will let you lose the alternator and e-start for a huge weight savings plus no flywheel weight!!!

http://www.build-stuff.com/x-cell.htm

[Bluegreen]

Very intersted in this thread, hopefully there are some people out there using these.

[kayaker43]

They are new but it seems the heavy users so far are the four stroke electric start dirt bikes and roadracers. I've been running one all summer in my DR650. I use the smallest 4 cell pack and tested it by seeing how many 5 second cranks I could get. It cranked for 30 consequtive starting attempts with two pauses to let the starter cool. The stock battery cranked 45 times but the last 10 were slower. That's pretty impressive since everyone reccomends using the 8 cell pack on a bike that big. Had I done that it would have endured 60 starting attempts!!!

Based on that I feel the 4 cell has about the same real world usable capacity as a 7 AH lead acid and the 8 cell is about the same as a 12 AH.

The two practical issues that may affect usability are that the voltage does sag a bit under 40 degrees but doesn't seem to bother people because it comes right back when the battery gets loaded and warmed. The other issue is that the user has to make sure the battery never runs down below 8 volts or its ruined. They hardly have any self discharge themselves so it would always be human error. Some people have a habit of shutting down with the kill switch and leaving the key on.

I wondered about the Vapor, better verify that it has no constant draw? Some electronics on newer bikes do and you need to keep it on a battery tender. These batteries do charge up faster because of the small size, and battery tenders work well with them.

You can buy a simple low voltage alarm for under $5.00 I use a simple digital volt meter to keep an eye on it and now wonder why all bikes don't come with them. Its so reassuring to know the state of charge and you could see well in advance any charging issues.

[Doctor_D]

Well, I just ordered the 4.6AH version.  I'll let folks know how it works out.

[dusterdude]

these things are talked about all the time on the dragbike.com forums,seems like a neat deal

[Doctor_D]

Well, I've already got a tracking number -- so quick shipping isn't an issue. 

[bradweingartner]

Be careful with those LiIon batteries. They have a bad tendency to explode violently when charged improperly.

Also, the contents of such cells spontaneously combust when exposed to air or water.

Makes the contents of Lead Acid batteries look downright benign.

[kayaker43]

bradweingartner,.. your information is old. There are issues like that with other types of lithium batteries but not these. Overcharging pops the end cap and releases pressure, no explosion possible. Your charging system can't go high enough to do this.

Lithium Polymer is real fussy, Lithium Ion is better but can still explode. Lithium Iron Phosphate doesn't do anything nasty. Lead acid batteries go off like a bomb if you make a spark while charging. VW bugs had them under the rear seat, I was charging and jiggled the clamp to make better contact. The battery went off and almost killed me, then I couldn't see for a day from the acid in my eyes.

Benign huh,!!

A123 cells = No nuclear fireballs,.. No spontaneous combustion,.. they're kind of boring actually. See youtube videos of a guy driving a nail through one, he just gets a big fizz.

[scottly]

bradweingartner,.. your information is old. There are issues like that with other types of lithium batteries but not these. Overcharging pops the end cap and releases pressure, no explosion possible. Your charging system can't go high enough to do this.

Lithium Polymer is real fussy, Lithium Ion is better but can still explode. Lithium Iron Phosphate doesn't do anything nasty. Lead acid batteries go off like a bomb if you make a spark while charging. VW bugs had them under the rear seat, I was charging and jiggled the clamp to make better contact. The battery went off and almost killed me, then I couldn't see for a day from the acid in my eyes.

Benign huh,!!

A123 cells = No nuclear fireballs,.. No spontaneous combustion,.. they're kind of boring actually. See youtube videos of a guy driving a nail through one, he just gets a big fizz.

Do you have any specs regarding charging algorithms?

[kayaker43]

Here's the A123 website http://www.a123systems.com/a123/products

Lots of other charging info out there but its mostly related to R/C planes and the chargers they use. Those guys are always exploring the limits of overcharge and over discharging.

Lucky for us its just coincidence that a 4 cell pack is right in line with what vehicle charging systems put out. The other lithium chemistries didn't work out like that.

[Bluegreen]

Here's the A123 website http://www.a123systems.com/a123/products

Lots of other charging info out there but its mostly related to R/C planes and the chargers they use. Those guys are always exploring the limits of overcharge and over discharging.

Lucky for us its just coincidence that a 4 cell pack is right in line with what vehicle charging systems put out. The other lithium chemistries didn't work out like that.

So we can just plug in a 4 cell pack and away we go?

[turboguzzi]

for total loss ignition these look fine but running a few dozen amps needed while cranking through those thin wires doesnt sound such a good idea to me.... that's why starter motor cables have 3/16-1/4" leads, no?

 but looks like it worked for you kayaker so what do i know?

TG

[kayaker43]

Yep,.. plug and play as far as the charging system but we are still figuring out how to relate them to lead acid as far as battery size.

 You can't compare amp hour capacity because these act like a battery 3-4 times their size. That's why I made them modular so you can add any capacity you need.

I chose not to use wires because I am aware of the voltage drop issues. A wire has a connection at the cell and another at the terminal you see, then you bolt to that making three connections. Fewer connections is better so I used a heavy copper strip directly to the cells. One less connection and as much current carrying capacity as your starter cables. My big thumper DR650 only pulls 25 amps. I'm hoping to get feedback from the SOHC crowd on starter draw but I know the 600 sportbike guys are getting away with 4 cell packs.

R/C cars routinely pull 80-100 amps through 10 and even 12 ga. wires, but there is a huge voltage drop. Those running their batteries in a tail section should beef up those long cables.

[scottly]

My big thumper DR650 only pulls 25 amps. I'm hoping to get feedback from the SOHC crowd on starter draw but I know the 600 sportbike guys are getting away with 4 cell packs.

SOHC 750 starter draws 120 amps...

[kayaker43]

I would think the 750 is not 120 amps continuous? My DR650 has a big spike but it settles in at 25 amps. My little inductive gauge doesn't show spikes.

Can anyone confirm the 750/550 amp draw while cranking?

The 4 cell pack is max 120 amps burst so 8 cell is 240 amps, still no problem. Many 600 sportbike guys are running the small pack for track days

[Doctor_D]

Mine arrived yesterday (ordered Sunday, arrived Wednesday - kudos).  Was securely packaged and undamaged on arrival. Read 11.7V dc out of the box - enough voltage to run right off the bat.

No electric-foot on my 836 -- as I have 2 perfectly good legs of my own, so I won't be able to comment on how it turns a starter.

[Bluegreen]

It turns a starter perfectly! I just hooked mine up today, hit the button and she fired right up. We'll see how it does over the next year of trips and traffic.

Edit: So I've done a few rips around town in traffic and has been working fine. Next test is night riding with headlight on.

[kayaker43]

OK guys,.. I'm clearing out my remaining battery packs before I head south for the winter. I can't get any more cells so this is the lowest price you'll ever see.

4 cell packs $65.00 each

http://www.build-stuff.com/x-cell.htm

[wannabridin]

Awesome deal!! I'm going to buy a 4-cell for my kick only build!! I'm only 26, so kick only for me!!! Make me appreciate a started for later in life

Correction: just ordered one now

[scottly]

OK guys,.. I'm clearing out my remaining battery packs before I head south for the winter. I can't get any more cells so this is the lowest price you'll ever see.

4 cell packs $65.00 each

http://www.build-stuff.com/x-cell.htm

I would like a 4 cell pack!

[MaaseyRacer]

A recently met a guy who built his own cell by disassembling one of these Dewalt batteries:
http://www.nationwidetool.com/p-168-dewalt-dc9360-36v-battery-pack-wnano-technology.aspx

They supposedly use A123 cells. He claims there are enough to make two batteries from one pack.

[kayaker43]

Those are good cells the same as I use. They get $118.00 shipped for enough to build 2 packs. My little assembly line averages one pack per hour and I only charge $130 for two packs.

For only $12.00 more I can save you at least a couple hours labor plus extra materials and you get a warranty. 

[scottly]

I have been running a 3 Amp hour lead-acid battery, in a kick-start application. That battery weighed about 3 pounds (I'll try to get an accurate weight when I get home), and cost about $50. For 20 bucks more, including shipping, I will shave another 2 pounds off my already light bike. The lighter it gets, the more difficult it is to shave pounds, so this will be easy and relatively cheap!

[MaaseyRacer]

Those are good cells the same as I use. They get $118.00 shipped for enough to build 2 packs. My little assembly line averages one pack per hour and I only charge $130 for two packs.

For only $12.00 more I can save you at least a couple hours labor plus extra materials and you get a warranty. 

Sounds good. I might do it after next week.

[vargas]

Yep,.. plug and play as far as the charging system but we are still figuring out how to relate them to lead acid as far as battery size.

 You can't compare amp hour capacity because these act like a battery 3-4 times their size. That's why I made them modular so you can add any capacity you need.

The problem with comparing capacity is that lead acid batteries are typically rated at the 20hr discharge rate... where as the A123 battery is rated at a 30hr rate (I believe). A battery's capacity will change as a function of how fast you discharge it.. this is modeled by peukerts equation.  If anyone is interested I can do a calculation to determine the A123 battery capacity at the 20hr rate so a direct comparison can be made.