Ballistic Performance Components - EV02 Batteries

If you read my post I said that I'd recommend 8Ah batteries. I just happen to be using 10Ah for my other project.

 

Jamie,

How many Ah are you using?

How do you balance the cells?

Do you solder to the terminals of the cells?

 

Here you go, this is a CBR1000RR by the way:

 

Thanks, JD.

While you have the digital camera out, can I put in a request for a detail shot of how you work the terminal connections?

 

Why no advertised Ah rating of the packs?

Does the battery have a balancer inside?

 

Because it's not really required, unless you plan on draining the pack completely dead every time you use it. Normally it's just maximum current capacity that you need to know. If you really need it for your application, the packs are made from cells with 2.5AH each.

No, once again not necessary. The cell chemistry does not require a balancing circuit. Balancers are only needed for older chemistries, the new technology has addressed that.

 

That's some pretty good info. Thanks

Just out of curiosity how do you charge the battery if it's dead and your bike won't start? Can you jump these batteries? Is there a different battery charger compared to something like a "Battery Tender" or 2a std trickle charger?

 

For the layperson, could you explain how this works, what it looks like, etc.?

What are the negative effects if the cells are not balanced?

Also, how does the stock charging system work with this type of battery?

Thanks!

 

Sorry, I removed my post. I didn't want to start an argument with Jamie, I respect him and what he's doing, this is an awesome idea for bikes. I'm using one in a different application.

I just think there should be balance leads on there, or a balancer on board. Just like RC car batteries. There's a small harness that would plug into a lithium charger that has a balancer inside. Either put one on the battery, which is cheaper, or put leads on there so people can do it themselves with an off the shelf charger.

Every chemistry of batteries go out of balance over time when they're put in a series configuration. I've tested hundreds of cells, from all sorts of different manufacturers, built quite a few battery packs (large and small). My side business involves testing batteries for people, assembling batteries, designing battery management systems and everything I've seen points to batteries going out of balance. Minute differences in the internal resistance of the cell can and will cause unbalance over time. This means, when one is at a higher capacity than another and you're charging, it will cause that one higher capacity to take charge quicker, and the voltage while the battery is being charged by the Regulator/Rectifier will cause one to get overcharged/overvolted. If you consistently overcharge, the cell dies.


Even if he's IR matching cells, the rate at which this unbalancing occurs, is increased, but it does happen over time. I know you're not constantly discharging the cells, it's just for starting and for inrush current when you turn lights on, the RR takes care of the rest of the current the bike needs. It'l take them right out of balance because IR is more of an issue the more current you draw, it'l drain more energy from one cell than another.



As for onboard charging, I'm not sure what the RR voltage output is at the max RPM of the engine. If these are lifepo4 cells, and the output is higher than 14.8V, you're going to be overcharging them. I'm not sure what he's using because there's no information on his website.

 

My battery tender has worked just fine. Standard motorcycle jump starting procedures should be use (if it's a car it should not be running, etc). Essentially the Lithium battery will behave exactly like your OEM battery.

The stock charging system works just fine. As mentioned above, you won't notice any difference in that area. About the only way you would be able to tell that it's a Lithium is because it's lighter and the engine will crank slightly faster. Otherwise everything stays the same.

Cell balancing is not an issue. The cells are similar to the ones used in cordless power tools these days - those are fully charged and discharged daily without any problems. On a motorcycle you pull a small amount of engery from the pack during starting. While the engine is running you are basically topping it off with a trickle charge. That scenario makes it highly unlikely that a cell would become unbalanced. Before assembling each pack, the cells are placed in a special fixture to ensure they are perfectly balanced to each other. With the chemistry used in these cells that is all that's required for the life of the pack. I've been running these for a couple of years now and they are functioning just fine.

 

If you read my post above you will see why this is not necessary. Lithium batteries have been used in motorcycles for several years and I am not aware of any problems with an out of balance condition. I think you are far over analyzing things. Don't forget that any automotive-type battery is discharged only a very small amount during normal operation. With that in mind I think you would have to agree that a balance circuit is overkill.

 

If you read my post above, you'll see I mention that most of the stuff I do with my business is involved with batteries. I've worked in Battery sales, technical support, design and assembly for the past 3-4 years.

I know you don't discharge them a lot, but you're cranking them at 100's of amps, which causes high amounts of energy to be put off as heat due to the IR of cells. Even just a few short seconds of discharge, over the course of a year (maybe more, maybe less, depends on the quality of the cell, and if they were IR matched before assembly). Just a few percent change between a couple cells will cause a lower state of charge for one. Then those with higher SOC's charge up faster than others, right after you've cranked the engine. They reach charge quicker. Voila, unbalanced pack. At first it won't matter, but the more pronounced it comes, you'll be overcharging one of those cells (maybe more).




Your pack will die due to one or two cells becoming overcharged/unbalanced well before the life expectancy of the pack. With a balancer, or occasionally balancing cells with an off the shelf hobby charger, you keep them all below overcharge and you'll get the full life of the cells.

 

If I could take a step back to the above, the FSM ('84 Edition) notes:

15.8A (no load) @ 2,000rpm
18.5A (no load) @ 5,000rpm

I didn't see a spec for the voltage regulator but it notes, when checking, to set the meter at 0A and 14-15V.

It does state that the 'regulator must divert current to ground when battery voltage reaches 14.0-15.0V'.

Is this Big Trouble in Little China or is the charging system A-Okay?

 

15V should be ok, I wouldn't go a ton higher with this chemistry. I mean, you can, it just won't last as long.

 

Interesting, thanks for the 411.

I wondering if installing an aftermarket voltage regulator (i.e. Accel or similar) is good insurance (if their spec notes 14.8v max) when running one of these batteries.

 

Not at all. As often happens out here on these forums, there is lots of misinformation being thrown around. The application of these cells when used as motorcycle batteries has been proven time and time again. If you install one of these batteries in your bike it will operate just like your OEM battery. In some ways even better. It's really just that simple!

 

FYI, for those interested: Ballistic EV02's have a balance port on them ...so does Shorai, Tekbattery, Motydesign, MBF Racing.

 

To balance or not to balance, that is the question...

If I could ask, does is hurt anything to have a balance port - are these an expensive item to add? I would think that there would be a benefit to having this built-in redundancy, to insure the battery's longevity.*

* Disclaimer, in no way am I an electrical engineer.

 

False information. Why MBF includes a balancer harness but then clearly state that balancing is not needed doesn't make much sense to me. Maybe it's to sell their $95 charger, perhaps? The Shorai packs also have a special connector - which you need their special charger for - and they also state it is not required.

I'm noticing this is becoming a series of questions aimed at false and ficticious information. These are not legitimate questions therefore I cannot produce an answer! If folks out there do not want cool stuff for their bike then asking questions until you find an answer that generates a negative response is a good idea. Constantly pounding away, searching for a reason not to do something, searching to make vendors of new products look bad, will ultimately cause those vendors to turn away from helping motorcyclists. I have to wonder: Is that what you want? It sure seems like it.

If you want something that works great, is lightweight, and saves space then a Lithium battery pack is for you!

 

JD, I get your opinion, sort of. It is not my intent to be a Doubting Thomas.

I very much appreciate all your efforts here. We are better off for them.

I do think my questions are legitimate. Why not add a balancing port so you can use a charger (unless I am not understanding this)? Also, adding terminals onto these packs would be most helpful, IMO. Again, I could be wrong about this, if you could take a photo of how you go about connecting these packs, maybe terminals are not required.

Half the fun for me, here on VFRW, is learning. Half the fun is helping. I don't have any interest in trying to prove someone wrong, apologies if my posts above came off this way.