LiFePo4 Battery test?

[seastar]

Randy, Pete
I am coming up on annual condition inspection time and thought I might replace my battery.
How are the tests coming on the Lithium Iron battery?
Is it ready for prime time?
Bill

[Pete D]

The ones we are testing in the aircraft here are doing ok. They don't seem to put out the current when cold quite as well as a lead acid. (below say, 40* F)

We still have some worst case scenario type testing to do yet though...


Pete D

[battman]

Lithium battery maker AEROLITHIUM will be at sun n fun
booth NE44

[randylervold]

Randy, Pete
I am coming up on annual condition inspection time and thought I might replace my battery.
How are the tests coming on the Lithium Iron battery?
Is it ready for prime time?
Bill

Bill,

Honestly, we are at a standoff. We LOVE the weight reduction, and we are having good luck with the starting performance though some owners haven't, but we just can't get comfortable enough with the potential failure modes to pull the trigger on it. Keep in mind the liability we take on if we approve it for SLSA aircraft and one blows up or starts a fire. About all we can do now is monitor the industry and the LiFePo manufacturers to see what more develops in the way of more definitive testing and/or more field experience in aircraft. I wish I had something more definitive for you but we just don't right now. Of course owners who have ELSA conversions may install whatever battery they wish.

[glickle]

All, While at Sun & Fun I visited with Andy the Aerolithium battery builder and he loaned me a 300Amp battery to try. He and his web site says these ARE Lithium IRON. The dimensions on this battery are even smaller than the Shorai and there is plenty of room in our battery boxes for the instalation, in fact its very small. While it did turn my cold engine over it was pretty much tha same power for a hot engine as the X2 lead acid and had trouble. I have retruned thebattery and Andy is not giving up and is building a custom 400 amp battery that will still fit and for me to try whch should be here next week. Will advise what I find. Best Gary

[John Hodges]

On starting battery ratings, the devil is in the details. There are some standard ways to figure cold starting amps, but not everybody uses them. That may be why a 300 amp battery doesn't perform any better than a 200 amp rated item.

[glickle]

Hi All, I spent some time with Andy of Aerolithium Batteries at Sun & Fun. ( www.aerolithium.com check it ut as there are you tube videos of some comparison motors/batteries) He says he has been developing electric cars for 6 years which led to his building these batteries: Here is what I found out about his batteries.

First and most important he states and also on his website his batteries are lithium IRON "high rate" cells not lithium ION.
He had split open three manufacturers batteries on display the Shorai, the Aerovolts and his. I must confess to my eye, the Shorai looked very cheesy as to the guts but looks great on the outside for finish, Andy claimed their flat cells are not high rate cells like his which are more costly. ( I treid 2 Shorai batteries one failed immediatley and shorted out the other was not as powwerful as the Extreme x2-14 so I sent it back.) Aerolithium batteries look just the opposite. The insides look more subsatntial but his case looks ameturerish.

Andy loaned me a 330 amp 2.5 lb battery to try on my CC and unfortunatley the power of that battery was about the same as the X2-14 Extreme Battery I have been using, so I took a pass. That said Andy was very accomodative and he was not giving up. I noticed the 330 amp battery was so small ( about half the size of ours) that there was plenty of room for a larger one. I gave Andy the measurements of our battery box and he then built a 16 cell 430 AMP 3.8 lb battery and sent one to me to test and ............................... IT WORKS! Much faster turn over and good starts when hot. I have stopped and started the hot engine 4 times in a row and still plenty of power . I only have a few hours and starts on it but will report what I find over the longer term.

Also here is some info regarding Lithium Batteries that I learned at the show from a few dealers:

1) Its critical that they not go below 12 Volts ( like leaving the master on or playing with your avionics without the engine) If they do drop below 12V then you need a special balancing charger to get them going again properly. If you run the lithium battery totally down it may not come back at all. A regular charger or letting the alternator do the job will probably ruin the battery. It makes a case for having a spare lithium with you just in case as the shelf life is well over a year without charging and they are so light weight just swap it out ( only draw back here is the cost as they are much more expensive that the lead acid, about 2.5x )

2) You can buy a cut off switch for those who are in the habit of leaving their masters on which will disconnect the battery if voltage goes below 12V in order to save it

3) Unless in an emergency you should never jump start a lithium battery as having all that amperage from the alternator hit the battery without a balanced charge will probably destroy the battery.

I suspect others on this forum know more about this and batteries in general and I am not endorsing or representing anything here other than passing on what I learned from three lithium reps ( Shorai, Aircraft Spruce re the Aero Volts and Aerolithium) while at the show. Clearly this line of batteies is developing quickly so would love to hear from anyone who knows more about these batteries and the technology. Best Gary

Here is a link to more than you might want to knwo about Lithium ION vs Lithium IRON http://en.wikipedia.org/wiki/Lithium...sphate_battery

[Pete D]

Gary,

You said you were able to see inside some of these batteries? What shape were the cells? Which ones had flat plates vs which ones had coils or round packs?

[glickle]

Gary,

You said you were able to see inside some of these batteries? What shape were the cells? Which ones had flat plates vs which ones had coils or round packs?

Hi Pete yes, the Shorai was flat plates and the Aerovoltz cylinders similar to the Aero Lithium, but was told the Aerovoltz are using non high rate cells. I have no verification of the high rate vs lower rate cells though. Below also is a chart and commentary from a website on Lithium Batterys ad the differences and Aerolithium says his are Lifepo4 Hope this helps Gary



Lithium iron phosphate cells have the best safety characteristics—long cycle life (up to 2000 cycles) and good availability. They are very suitable for high discharge rate occasions such as EV (including e-bike, electric scooter, and electric car), power tools, UPS and solar energy system.

COMPARISON DATA AMONG VARIOUS LITHIUM BASE BATTERIES:

Battery	LiFePO4	LiCoO2	LiMn2O4	Li(NiCo)O2
Safety	Safest	Not Stable	Acceptable	Not Stable
Environmental Concern	Most Enviro-friendly	Very Dangerous		Very Dangerous
Cycle Life	Best/ Excellent	Acceptable	Acceptable	Acceptable
Power/Weight Density	Acceptable	Good	Acceptable	Best
Long Term Cost	Most Economic/ Excellent	High	Acceptable	High
Temperature Range	Excellent (-20C to 70C)	Decay Beyond (-20C to 55C)	Decay Extremely Fast over 50 C	-20C to 55C

[carlconti]

Legend (excuse my using that brand name here) now offers a lithium battery as an option. Does anyone know what battery they are using?