LiFePO4 revisited --- EarthX ETX36C

[BillyDoc]

Well . . . my OEM battery finally croaked, and I've been itching to try the new lithium iron phosphate technology, so after some searching I found what I hope is a good replacement. It's a product from (gasp!) an actual American company, EarthX, and it has some nice tech inside. Specifically, built in BMS circuitry (Battery Management System) that keeps the cells all balanced and guards against overcharging.

Previous posts on here have complained that cold-weather starting was "inadequate" with earlier examples of LiFePO4 technology, but those were much smaller batteries than the one I just fitted in my NT. I'm hoping that the extra power the ETX36C has will overcome internal high resistance when it's cold . . . but I may not get to test that as I live in Florida (and so far so good). The initial start after the bike sat for over a week as i waited for the new battery was instantaneous! The temperature was 60 degrees F though.

The case on this battery drops snuggly into the OEM plastic case on the NT, so there were no spacers required or other problems like that. Swapping out the old for the new was extremely easy with no "customizing."

This battery is rated at:

Voltage: 12 V
EqAh: 36
Pulse Crank Amps (PCA): 680A
Cold Crank Amps (CCA): 405A
Maximum Charge Voltage: 15 V
Max Charge Amps: 10A
Weight: 3.5 lb (1.5Kg)
Dimensions: 150mm(L)x86mm(W)x115mm(H)

This battery cost twice what the OEM battery sells for, but it's service life is rated as 3 - 8 years, so it's hopefully cheaper in the long run.

So far, I'm extremely pleased!

BillyDoc

 

[SCBWV]

Here's a link to a YouTube video that explains the cold weather characteristics of lithium iron phosphate batteries. Pretty interesting. http://m.youtube.com/watch?v=OBfvR1EJJBk&desktop_uri=%2Fwatch%3Fv%3DOBfvR1EJJBk

 

[charlie b]

Lithium batteries are all cold blooded. If you have a way to pull some current from them, then they self heat pretty nicely. But, there can be problems with some bikes that have a low voltage cutoff in the computer. They won't let you crank the engine if the voltage is below a certain level. For those cases you need to get a higher cell count battery, or, wire in a bypass so you can crank the engine.

Lifetime is the good part. As long as they are kept balanced, are not run too low, and are not overcharged they will last almost forever. Heat will kill them, but, it takes a lot of heat to do that.

 

[elizilla]

I have a LiFe battery which I installed in my Super Tenere. The bike has a headlight cutout that keeps the headlights from coming on before the bike is started; I assume for optimal results with the stock, conventional battery. I got around this by relaying my heated grips so they come on with the ignition and don't wait for the engine. I just turn the key on, the grips come on with the key because I never turn them off in winter, and the battery warms up while I am backing the bike out of the garage.

 

[Warren]

$350 for the EarthX is pretty rich. Hopefully you get many years of life from it.

 

[elizilla]

The Shorai I put in the Super10 was about $150, still pretty rich, but the OEM battery died about two months after I got the bike. I didn't want to argue with the dealer about whether my farkles voided the warranty, and I certainly didn't want to undo all my wiring just to pass their casual inspection, so I just bought my own replacement battery. And since I had recently seen the LiFe thing I decided I'd try it.

It was in there for all of 2012, when I was still able to ride the bike and I put 15K on it, and it's been in there all of 2013 when occasional friends have exercised the bike for me. So, two years, and no problems yet.

I didn't buy the fancy trickle charger. I don't charge it. It lasts just fine without. And it's now had a year each of different styles of usage. One year where it was never parked for more than a few days, and one year of being parked for months at a time.

 

[BillyDoc]

I've been waiting for freezing weather to see how this new battery starts the bike, and it was 28 degrees F this morning in Pensacola, which is probably as cold a test as I'm likely to get. Climate change, and all that. The bike was outside all night. I'm very happy to report that the bike started up almost instantly, just like at 60 degrees. I didn't need to do the dance shown in the video posted by SCBWV, not even close, it just started. Of course, another ten degrees colder might have made a considerable difference.

This battery technology is reported to be able to deliver a lot more amps because of low internal resistance, and I believe it. Since I installed it in my NT I've not had the bike "crank" and start even once. It just starts to run in a fraction of a second! I like that.

Bill

 

[Rich]

The likely reason this one works OK in the cold where the recommended Shorai routinely does not is because the model you got is much larger capacity than either that Shorai or the OEM. In watt-hours, it's larger than the battery used to start the 360 cubic inch engine in my airplane.


When my Shorai failed after a year, I took my OEM battery, installed it in the NT and started the bike right up. It had not been on a charger or anything. It just sat lonely and ignored on the carport shelf for that same year.

 

[BillyDoc]

The likely reason this one works OK in the cold where the recommended Shorai routinely does not is because the model you got is much larger capacity than either that Shorai or the OEM.

That's precisely why I picked this particular battery, Rich, I was forewarned by the experiences of others on this forum. There are also data available showing how precipitously the internal resistance rises in cold weather, and it isn't good with this technology. This problem is overcome by adding capacity. In terms of capacity, the ETX36C is MUCH larger than the battery EarthX actually recommends for the NT. But, since the case size worked, I went with this monster. I was also influenced by the (presumed) long life of this technology, and I love the fact that a BMS is built in.

The extra capacity is also insurance against problems like an alternator failure in an awkward place, in my view, and worth the cost.

Bill

 

[Rich]

It is interesting that the EarthX has more smarts built into the battery itself and there is no special ceremony described for cold-weather operation as with the Shorai.

 

[BillyDoc]

Update:

It was 19 degrees F at my house in Pensacola this morning, and the NT started right up on the first crank, as before but the cranking speed was slightly slower. Again, I did nothing but put it in neutral, switch it on and push the starter button.

Now that we've done the battery test properly, would you Yankee gentlemen please keep your weather up north, where nature intended it to be? My fingers still hurt from my ride in to work this morning, and that with grip heaters.

Bill

 

[charlie b]

Thanks for that info. Looks like I will be changing over next time I need a battery.

 

[Rich]

Putting the super-oversized battery may be the way to go. But I can say that using the recommended Shorai didn't work for me in the NT. First of all that, trying multiple starts to warm the battery didn't work at all. If it didn't crank satisfactorily on the initial crank it just got weaker with every try. Plus those voltage dips shown in the video are plenty severe to reset all your counters (clock, trip odo's, fuel mileage accum.), even when it does start semi-normally.

Now this was one battery from one manufacturer, so the sample size is limited. And the temperatures involved for me were in the 30's (Fahrenheit). So maybe there's different behavior when its considerably below freezing.

Being kind of stupid, I'll be giving the EarthX a try in my FJR shortly. Unfortunately, I can't cram the way-oversize version into the FJR battery compartment, so the biggest one is about 50% oversize in terms of equivalent amp-hours. Why do this? Well, I can afford to waste a bit more dough, if that's what it comes to. And I'd like to get a bit more room in the relatively tight confines of the FJR battery compartment. And it cuts over 7 pounds of weight from this area, which is fairly high in the chassis (it's mounted up in the front right fairing). Worst case, it's a waste of time and I'll use it for something else and go back to the OEM battery.

 

[charlie b]

I think the key here is NOT to use the recommended version. Get at least one size larger.

 

[Rich]

I think the key here is NOT to use the recommended version. Get at least one size larger.

EarthX has limited choices of case size. The largest capacity one that will fit in the FJR battery compartment IS the recommended one. The FJR does have one feature that helps. Short term voltage excursions (such as disconnecting the battery to install a Slime pump pigtail) do not cause counter or clock resets.

 

[Rich]

An update on the EarthX battery in my FJR: I've had 2 cold-morning opportunities so far: 33 degF the other day and 24 this morning. Started right up both times. No, it's not on a battery tender.

 

[Bear]

I heard that "Battery Tender" is now marketing a battery. It is hyped to be quite the battery. A friend of mine attended a motorcycle show and they had them there.

 

[charlie b]

Don't know what the mfgs say but using a battery tender on a Lithium battery is not usually recommended. One of the advantages of the lithium is they don't lose charge over time near as much as other compositions. Some mfgs do recommend that if you put them in storage you should discharge them to about 75%, but, I have had LiPo batteries fully charged that have sat for over a year and are still at or above the rated voltage. YMMV

 

[Rich]

While the LiFe batteries have very low self-discharge rates, many bikes (this includes the NT and FJR) have a "trickle-draw" to keep things like the clock and trip odometers valid. EarthX states that some battery-maintainers are OK to use, as long the float voltage is not below 13.3 volts and there is no desulfation cycle. They specifically mention the Battery Tender Jr. as being OK, but other Deltran units are not.

 

[rc_heli_nut]

I purchased a Shorai for my 81 CM400A. Anxious to try it out soon.

I use Lithium Polymers in all my RC aircraft, so this type of battery and it's characteristics are familiar to me.

Charged it using an FMA Cellpro 4S set for the A123 mode, charging solely through the balance port, then shelved it for 2 months.

After those 2 months, connected it to charger again, and it was still at 100 percent.

Anxious to see how it works in use.

Brad