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How I installed a LiFePo battery and saved 11lbs!

ChiefPilot

Well Known Member
This past December saw the first condition inspection on my -6A. Aside from the inspection, I had decided to use this time to install some upgrades. One of the upgrades was to replace the 15.7lb PC-680 battery with a 2.7lb Shorai LFX18L1-BS12 LiFePo battery.

Much has been written here and elsewhere about the merits of Lithium-Iron-Phosphate batteries (see this thread for a great discussion). Rather than re-hash the discussion around the tech, I wanted to share how I installed this battery in my RV without making any changes to the airframe, wiring, or battery box. I hope someone finds this helpful!

Operation
Since the first question I'm sure many will ask is "How well does it work?", I'll start with that. In short, I can tell no difference in normal operation between this battery and the PC-680. I have an IO-360-B1B w/8.5:1 pistons and dual P-mags and this battery spins the Hartzell BA prop with the same gusto as the PC-680, if not more. I've had it in weather down to -1ºF and it has performed as expected. I'm continuing to watch this carefully, as I have only about five hours of running time so far but I don't expect any surprises. I do like the weight savings however!

The Installation
The first step was, of course, to obtain said battery. I ordered the battery directly from Shorai and received it a few days later.
11633820826_61cffd37fd_z.jpg


I had previously removed the PC-680 from the aircraft and compared the two side by side. Clearly, the Shorai battery is significantly smaller - but the weight difference is even more dramatic. Not wanting to count on published specs, I measured both batteries myself. The Shorai matched the published specifications in all respects, and indeed weighed only 2.3lbs. Interestingly, the only discrepancy with published specs I found was with the PC-680 - the Odyssey site claims the PC-680 weights 15.4lbs but mine measured 14.0lbs.

11633286133_d21099067b_n.jpg
11633826086_59deefffb8_n.jpg


One of the goals for this upgrade was to be able to preserve the ability to do a "drop-in" upgrade. This preserves the possibility of going back to the PC-680 at some point in the future, and also eliminates changes to the airframe/FWF configuration. Since the Shorai battery is significantly smaller than the PC-680, that means that an adapter is needed to secure the batter within the larger space of the PC-680 battery box.

Enter a large chunk of UHMW plastic. I love working with this stuff - it's relatively cheap, it's easy to mill, and it's reasonably lightweight. Certainly other materials could be used - aluminum, or perhaps even wood - but I had envisioned starting with UHMW and so that is the path I went down. The original chunk looked like this:
11633831116_178ef2ba68_z.jpg


I used this material to make two "end caps" that positioned the battery in the correct location with the PC-680 box in all three axis (fore/aft, left/right, and vertically). This allows the battery to be secured in the box by the same aluminum bar and AN bolts as the PC-680. This approach also means that the battery cables reach the terminals without modifications.
11633052185_ea4d8b9208_n.jpg
11633836066_2efef8c85d_n.jpg


The actual installation took just a couple of minutes: place the blocks into the battery box, place the Shorai battery into the blocks, install the battery straps, and then finally attach the battery cables.
11633837936_edaac2b55b_z.jpg


The last part of the process was updating the logbook along with weight and balance information. Overall weight savings was exactly 11lbs; I'm sure this would be a bit more for folks who have a heavier PC-680. Since my RV has the training wheel up front along with a constant speed prop, saving 11lbs on the firewall was a welcome change.
 
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Excellent report. Can you tell us more about the engine that this battery has no trouble starting? Please include size, compression ratio, mags or EI etc.

I have been considering the Shorai as well. I'm not flying yet so there's no immediate plan to order the battery yet. But I thought I would need the biggest battery Shorai makes which does not fit in the battery box designed for the PC680.

Bevan
 
Excellent report. Can you tell us more about the engine that this battery has no trouble starting? Please include size, compression ratio, mags or EI etc.

Sure - it's an Aerosport Power IO-360-B1B w/dual P-mags and 8.5:1 pistons. It typically starts on the second or third blade when cold, or much later if warm and I ham fist the throttle/mixture during a hot start. The new battery hasn't helped my hot-start skills, unfortunately, and instead behaves just like the PC-680 it replaced :eek: .
 
Questions...

Is your plane 'electrically dependent' (meaning the your avionics)?
If so,
How does the actual total energy in the battery compare to the SLA you removed?

The reason I ask is: I keep reading that almost all the various lithium tech batteries being sold for starting duties use 'equivalent capacity' ratings. If I've read correctly, this means they have the same starting capacity (high current drain) but often have significantly lower total energy (loose interpretation: they won't power avionics as long).

I hope it can handle the lower drain duties; I'd like to save that weight, too.

Charlie
 
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Is your plane 'electrically dependent' (meaning the your avionics)?
If so,
How does the actual total energy in the battery compare to the SLA you removed?

The reason I ask is: I keep reading that almost all the various lithium tech batteries being sold for starting duties use 'equivalent capacity' ratings. If I've read correctly, this means they have the same starting capacity (high current drain) but often have significantly lower total energy (loose interpretation: they won't power avionics as long).

I hope it can handle the lower drain duties; I'd like to save that weight, too.

Charlie

I have a Dynon D10A EFIS + D10 EMS; the EFIS has an internal battery pack which will run the unit for several hours. The Pmags provide their own power, so the engine isn't dependent on the battery to continue.

The LiFePO batteries have a very different discharge curve than lead acid batteries and so a direct comparison is difficult. A lead acid battery drops the voltage throughout it's discharge voltage whereas a LiFePo battery does not. If your GPS/COM requires 11.0 volts to function, an "equivalent capacity" LiFePo battery will likely power it longer than a lead acid battery since it will provide more time above 11.0 volts than will the lead acid version.
 
The reason I ask is: I keep reading that almost all the various lithium tech batteries being sold for starting duties use 'equivalent capacity' ratings. If I've read correctly, this means they have the same starting capacity (high current drain) but often have significantly lower total energy (loose interpretation: they won't power avionics as long).

The ratings you are are speaking of are -

Cold cranking amps - the amount of amps the battery can supply in a maximum current draw condition (starter motor).

Amp / Hr rating - The number of hrs a fully charged batter can supply a current flow of 1 amp. I.E, the aviation standard Concord CB-25 battery is rated at 25 amp / hrs. A fully charged one should be able to supply 5 amps for 5 hrs (amps X time). In reality it is usually a bit less than rated because of losses with age, etc.

The cranking amps rating of the PC-680 is very close to the CB-25 but the amp / hr rating is lower (about 17 if I remember right). I don't know what the Shorai cranking amps rating is, but it sounds like it is also very close to the others if the engine cranks well. I would imagine that the amp hr rating might be even lower tough (is it listed in the supplied documentation?)

One caution comment to adopters of this type of battery...
I also am interested in experimenting with some of the new battery technologys for the weight and space savings potential now that the technology has matured quite a bit, but there are serious fire dangers with this type of battery. I would not install one without building a fully sealed fire proof case to contain it. Even then, I would at least consider adding a temperature probe to monitor what is going on inside that box.
 
One caution comment to adopters of this type of battery...
I also am interested in experimenting with some of the new battery technologys for the weight and space savings potential now that the technology has matured quite a bit, but there are serious fire dangers with this type of battery. I would not install one without building a fully sealed fire proof case to contain it. Even then, I would at least consider adding a temperature probe to monitor what is going on inside that box.

While that is certainly true of Lithium-Ion batteries, lithium iron phosphate batteries do not have the same thermal runaway failure mode. I avoided the lithium ion batteries precisely because of that reason.

More info: http://www.batterystuff.com/kb/articles/battery-articles/lithium-battery-overview.html
 
Good answer!
Thanks for the info and pictures. Nice work.

I am on the other end of the weight problem. I have a O-320 (9A)and will have a FP Catto prop. I have the box built for the P-680 which makes the nose lighter yet. I like the idea of reducing weight - 11 lbs is a big savings, but maybe I won't be able to carry any baggage! I haven't done CG calculations yet, but if I keep reducing weight on the front, I can get aft heavy quickly. I also converted from a tail wheel and did not remove the wheel sleeve from the tail section.

While that is certainly true of Lithium-Ion batteries, lithium iron phosphate batteries do not have the same thermal runaway failure mode. I avoided the lithium ion batteries precisely because of that reason.

More info: http://www.batterystuff.com/kb/articles/battery-articles/lithium-battery-overview.html
 
Rock wood, like you, my 9A needs weight in front, rather than rear. All my sample W/B calcs show problems when I fill fuel and take a guy rather than my wife. Adding the Antiaerosplat steel bar helps. I like this low weight battery technology especially if the thermal dangers are not there.
I am thinking of mounting one somewhere near CG mid point for backup.
I used to hand prop regularly in my Luscombes. Don't think I would try it on the Catto hanging on the RV
 
Sorry to go off topic a bit but I just ran my numbers for my 9A and with one gallon of fuel, a couple of 250 pounders, and 75 pounds of luggage, I'm still within the aft CG limit. I have a Catto and an O-320. It's pretty tough for my airplane to exceed the aft CG limit.

I now return you to your regularly scheduled programming.
 
Kelly, that is good news. I want to at least use the p-680 and really like the LifePro. The way The Chief installed is exactly like I would since I have the battery box already mounted.

Thanks for running the numbers. My worry was a 200lb pilot, 135 passenger, full fuel, and 50 -75 lob of baggage. Since I don't have my data points to do CG calculations, I was worried that getting to light up front would be a problem.
 
Kelly, that is good news. I want to at least use the p-680 and really like the LifePro. The way The Chief installed is exactly like I would since I have the battery box already mounted.

Thanks for running the numbers. My worry was a 200lb pilot, 135 passenger, full fuel, and 50 -75 lob of baggage. Since I don't have my data points to do CG calculations, I was worried that getting to light up front would be a problem.

For my airplane, this loading puts my CG at 82.63" which is more than 2" forward of the aft limit of 84.84". The worst case with zero fuel, my CG ends up at 83.50 with this loading.

You have no worries.
 
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This past December saw the first condition inspection on my -6A. Aside from the inspection, I had decided to use this time to install some upgrades. One of the upgrades was to replace the 15.7lb PC-680 battery with a 2.7lb Shorai LFX18L1-BS12 LiFePo battery.

Much has been written here and elsewhere about the merits of Lithium-Iron-Phosphate batteries (see this thread for a great discussion). Rather than re-hash the discussion around the tech, I wanted to share how I installed this battery in my RV without making any changes to the airframe, wiring, or battery box. I hope someone finds this helpful!

Operation
Since the first question I'm sure many will ask is "How well does it work?", I'll start with that. In short, I can tell no difference in normal operation between this battery and the PC-680. I have an IO-360-B1B w/8.5:1 pistons and dual P-mags and this battery spins the Hartzell BA prop with the same gusto as the PC-680, if not more. I've had it in weather down to -1?F and it has performed as expected. I'm continuing to watch this carefully, as I have only about five hours of running time so far but I don't expect any surprises. I do like the weight savings however!

The Installation
The first step was, of course, to obtain said battery. I ordered the battery directly from Shorai and received it a few days later.
11633820826_61cffd37fd_z.jpg


I had previously removed the PC-680 from the aircraft and compared the two side by side. Clearly, the Shorai battery is significantly smaller - but the weight difference is even more dramatic. Not wanting to count on published specs, I measured both batteries myself. The Shorai matched the published specifications in all respects, and indeed weighed only 2.3lbs. Interestingly, the only discrepancy with published specs I found was with the PC-680 - the Odyssey site claims the PC-680 weights 15.4lbs but mine measured 14.0lbs.

11633286133_d21099067b_n.jpg
11633826086_59deefffb8_n.jpg


One of the goals for this upgrade was to be able to preserve the ability to do a "drop-in" upgrade. This preserves the possibility of going back to the PC-680 at some point in the future, and also eliminates changes to the airframe/FWF configuration. Since the Shorai battery is significantly smaller than the PC-680, that means that an adapter is needed to secure the batter within the larger space of the PC-680 battery box.

Enter a large chunk of UHMW plastic. I love working with this stuff - it's relatively cheap, it's easy to mill, and it's reasonably lightweight. Certainly other materials could be used - aluminum, or perhaps even wood - but I had envisioned starting with UHMW and so that is the path I went down. The original chunk looked like this:
11633831116_178ef2ba68_z.jpg


I used this material to make two "end caps" that positioned the battery in the correct location with the PC-680 box in all three axis (fore/aft, left/right, and vertically). This allows the battery to be secured in the box by the same aluminum bar and AN bolts as the PC-680. This approach also means that the battery cables reach the terminals without modifications.
11633052185_ea4d8b9208_n.jpg
11633836066_2efef8c85d_n.jpg


The actual installation took just a couple of minutes: place the blocks into the battery box, place the Shorai battery into the blocks, install the battery straps, and then finally attach the battery cables.
11633837936_edaac2b55b_z.jpg


The last part of the process was updating the logbook along with weight and balance information. Overall weight savings was exactly 11lbs; I'm sure this would be a bit more for folks who have a heavier PC-680. Since my RV has the training wheel up front along with a constant speed prop, saving 11lbs on the firewall was a welcome change.

So how is your new battery working out?
 
While that is certainly true of Lithium-Ion batteries, lithium iron phosphate batteries do not have the same thermal runaway failure mode. I avoided the lithium ion batteries precisely because of that reason.

More info: http://www.batterystuff.com/kb/articles/battery-articles/lithium-battery-overview.html

Well, technically true, but they do have a different thermal runaway mode. RVBuilder2002 suggested a thermocouple in the battery, I second that recommendation. The condition of full charge and higher than cell voltage constantly applied across the terminals in a hot environment is the worst case. They will still run away, but maybe not burst, or burst and spew the exothermic fuel from the case. It is hard to get exact data from the battery guys on constant voltage applied and we use 14.7 +0.2 VDC and not 13.8 + 0.2 VDC like cars/motorcycles. Look on the A123 website or other cell suppliers for their recommendations for maximum voltage.

I am all for the new technology and think it will be a big improvement in the long run, but drop-in replacement without specific (not marketing logic) data from the manufacturers on the potential failure modes deserves caution.

Thanks for sharing - be safe!!
 
It is hard to get exact data from the battery guys on constant voltage applied and we use 14.7 +0.2 VDC and not 13.8 + 0.2 VDC like cars/motorcycles. Look on the A123 website or other cell suppliers for their recommendations for maximum voltage.


Thanks for sharing - be safe!!

It would seem to be a good idea to replace the voltage regulator to set the system voltage to the lower value. IIRC the specs call for a maximum voltage a bit less than the 14.7 we SE with lead acid batteries it is replacing. With the tolerances usually a part of these sorts of things you might still be ok but safety margin is definitely lower. Finding a regulator made for these sorts of things shouldn't be too hard but I haven't hit the Web looking yet.
 
Thought I'd post a quick update - I've been flying with this battery now for close to 60 hours and have had zero problems with it.

One of the "real" tests was rather inadvertent - I left the master switch on while visiting a remote airport. You know that sinking feeling you have when you go to hit the master switch and it's already on? Yeah. So anyway, a friendly soul had a charger I could use and about 25 minutes later the battery had enough juice to spin the prop and start the engine.

I don't see going back to the PC-680 any time soon - the Shorai battery does everything I would ask of it and does it while shaving 11 pounds off empty weight.
 
Ballistic Performance Components...

Let's not forget our friends in Wisconsin & South Carolina (USA) who make and sell LiFePO4 batteries. I've been using the 16 cell EVO2 for about 14 mos as I recall. Amazing starting power. Good domestic alternative to consider if you decide to ditch the lead acid and save 10-12 lbs!

http://www.ballisticparts.com/products/batteries/batteries.php
 
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Neither of those batteries fit the PC-680 battery box, which was a prime consideration for me; as stated, I wanted the ability to go back to the PC-680 should the need arise.

While I'm sure both Super-B and Ballistic make fine batteries, they did not meet the requirements for my project.
 
So a quick update. It's been ~200 hours and a full year since I installed the Shorai battery and ... nothing. No issues with it, no problems starting (well, except when I left the master on for the day - oops - but even then 25 mins on a portable charger and we were good to go), just nothing out of the ordinary.

At this point, my next step with the battery will be to design and fabricate a custom box for it instead of the PC-680 box. It's proven to me that it's a solid choice, and I think I can save perhaps another pound or so with a specialized box for the battery.

I'd definitely do it again; in fact, doing the build over, I would do it from the start.
 
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Thanks for the follow up posts

Brad,

Thanks for the follow up posts. Please continue them as you add time to the install. I think you are on to something here.

-Vic
RV8 Firewall forward/engine
 
Time for another update. It's been an additional 178 hours on the Shorai battery and it's still going strong.

This battery is now over two years old and has well over 400 flight hours on it, so it's probably a good time to measure how much capacity it has remaining. This is done by measuring the no-load voltage of the battery following a full charge and comparing it to the chart of values provided by Shorai.
shorai_V_table.jpg
In this case, my battery had a no-load voltage of 14.1v, indicating that it still retains approximately 98% of it's capacity.

A word on charging... As you probably know, the Shorai battery does not have a BMS circuit as some others do but does have a port for a balancing charger to plug in. For as long as I've had the battery, I've plugged in the balancing charger to "top off" the battery when I change the oil. I have yet to have an instance where the charger doesn't find the battery in a fully charged and balanced state almost immediately.

I remain completely pleased with this battery - it's light weight, minimal marginal cost over the stock PC680, and reliable performance continues to impress.
 
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500+ hours and still going strong

Almost forgot to update this!

It's been another 9 months of trouble-free operation on the Shorai battery. At this point, I've decided that it's good to go and noticed that the PC-680 battery box it was contained it was a bit heavier than needed. A custom designed aluminum box made from .032 2024 sheet was a pound lighter while still supporting 25lbs (10x the battery weight) in multiple directions.

Several people have contacted me regarding the Shorai's lack of BMS and wondered if I was concerned about it. The short answer is, no, not in the least. My alternator has over-voltage protection, and my EMS starts chirping if the voltage rises about 14.5 volts which would provide plenty of time to swipe the alternator switch off. The battery is external to the cockpit anyway and vented so even in the event of an outgassing, the fumes wouldn't be inside.

I've got a new Shorai battery to replace this one at some point in the near future; I think the battery has given yeoman's service and I'm tempted to put the new one in then perform a destructive test on the old one by overcharging it in a safe environment. I need a good design-of-experiments however to get best value of of such an activity so it will have to wait a bit longer.
 
How about an Osh, hot day test?

Excellent documentation of use. Regarding a test. I have been thinking about a few things that might combine for a pass/fail test. Lets call it the Conga Line.

It is a hot day in OSH. Sitting in the sun, but having left something on, the battery is down so low it won't spin the engine and it is getting time to go. So, a little charge (undefined as yet) or jump start, then get in the taxi line and get good and hot while charging at idle (this will take a power supply), a temp ramp until take off. Then a worst case, 16.4 volts - up to 60 amps charging - battery demand will decide the charge rate. Then maintain the ambient temp (climb) and keep at 16.5 volts to track the internal battery temperature.

Selection of temp ramp rate, time in taxi, idle charge voltage, then terminal temps and amps at 16.4 volts all need better definition. Maybe increase to worst case plus x degrees just to give some margin. If it passes the test, (does not exotherm) then we have a winner.

A battery blanket and a few thermocouples (to monitor) can provide the heat/temp, a variable power supply (up to 60 amps) can provide the charge power. Maybe a resistive battery tester for the initial discharge cycle to simulate a start.

Just a (long) thought for an abuse test.
 
After 1.5 years of regular use (120+ hours) including one deep discharge event and recharge by the alternator, I finally bought a balance charger to use at annuals. After about 15 min of charging with this new charger, it went into standby mode. I'll take that as a good sign. With the battery on the engine side of the firewall, and a layered electrical bus system, over-voltage control, alarms, voltmeters, ammeters and a standby alternator, I feel very good about this technology. Would do it again.

Bevan
 
I just installed an EarthX in my RV6 and used a similar strategy to shim the stock Vans battery box just aft of the firewall. I just finished printing a polycarbonate replacement that should drop a few more pounds from the overall install.

open
 
Lithium Ion Phosphate Battery

I bought this one online and it's an excellent drop-in replacement for the PC680.
yzafsdL.jpg


There are several advantages to this type of battery, the biggest being it's a lot lighter:
cl4tKgW.jpg


But there a lot more advantages as well. To begin with, it has a full 20aH capacity, whereas a L-A or AGM style battery will cut off much sooner at about 30% of it's total capacity rating - so you have more real capacity. Also, these have overvoltage, undervoltage and reverse polarity protections built in. It will lose no more than 3% of it's full charge sitting for a year and doesn't need a battery minder and will cycle up to 5000 times before dropping to 80% fulll capacity in it's life cycle, which likely exceeds my needs for a battery. They also are not affect by ambient temperature the way a LA battery is. It can be colder than a brass toilet seat on the shady side of an iceberg, but this will still give it's CCA rating; lead acid batteries will not. I wanted to add that this particular battery has a Cold Cranking Amp rating of 200A, which is the 30 second discharge capacity of the battery and what you'd want to compare for those cold morning starts. Some batteries list a PCA rating, which is it's 5 second Pulse Cranking Ampacity, however most batteries are not rated for this, but rather CCA.

One other thing: DanH, if you're reading this...I figured out how to resize photos. Thanks for spurring me to do this. :)

Lot's of reasons to do this. Oh, and it was $289 retail. I got an additional 20% discount from these fine folks as an apology for a week delay in shipping (address on the battery), making this a very low cost option as well with excellent warranty. Understanding the cost and advantages, I don't see any reason to stick with a lead acid based battery.
 
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Lithium Ion vs LiFePo4

Hi Ron, I thought Lithium Ion batteries were a bit dangerous, which is why EarthX and others are using LiFePo4?

Here's a Lithium Ion battery that has been overcharged:

https://www.youtube.com/watch?v=k5f0VCoFuFM

Does the case have any containment features in case of issue? Seems like overcharging it could cause trouble.


Never mind - looked at their website, they say it's lifepo4.
 
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Ron,

If the label on the battery means what it says, *please* do some homework. If it's really a lithium *ion*, and not lithium *iron* phosphate, you're gambling your airplane (and you) on the same tech that's in flaming laptops, cell phones, and 'hover boards'.
https://www.google.com/webhp?source...UTF-8#q=lithium+iron+phosphate+vs+lithium+ion

Charlie

edit: Looking closer, it seems to be labeled both ways. If it's really lithium iron phosphate, it's just time to be sure it's got a battery management module built in, instead of raw panic time. If there's not intelligent battery management built in, well, back to panic mode....
 
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Guys, the actual chemical make up is LiFePO4. It still has Lithium on the anode and uses an ion charge to operate. They've changed the name to "protect the innocent", (or get better marketing, I dunno), but electrically, it's still a lithium ion battery, but using improved technology to prevent spontaneous combustion, or in engineering terms, a spurious exothermic reaction due to high, sustained discharge on the cathode where the lithium (a transition metal) will ignite, much like magnesium, if you've ever seen it burn.
 
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edit: Looking closer, it seems to be labeled both ways. If it's really lithium iron phosphate, it's just time to be sure it's got a battery management module built in, instead of raw panic time. If there's not intelligent battery management built in, well, back to panic mode....

Charlie, if you read my previous post, you'll see that what I described as the advantages of this battery are functions of a battery management system. In reality, every cell has a MOSFET controller built into it, so technically, it's an array of BMS's. If you're still concerned, please do read their website documentation and watch the videos. My guess is that any battery vendor wanting to make it in this current market will have many of the same features. I very diligently considered about 8 different batteries on the market. The EarthX has a output fault signal that you can tie into your EFIS to be informed of a battery fault, but I thought for the significant price difference, I'd just stick with voltage and amp indications.
 
Charlie, if you read my previous post, you'll see that what I described as the advantages of this battery are functions of a battery management system. In reality, every cell has a MOSFET controller built into it, so technically, it's an array of BMS's. If you're still concerned, please do read their website documentation and watch the videos. My guess is that any battery vendor wanting to make it in this current market will have many of the same features. I very diligently considered about 8 different batteries on the market. The EarthX has a output fault signal that you can tie into your EFIS to be informed of a battery fault, but I thought for the significant price difference, I'd just stick with voltage and amp indications.

Ron, you are going to install this in your RV12 with the PM alternator?
 
I did finally find the info about their BMS in their tech docs. Shame that they label the battery as a 'lithium ion' battery. It's technically correct, since ions are involved, but the term is typically reserved for the ones that can light you up, in a bad way.

I also noticed that it's a 16 cell battery, in series-parallel configuration. Running cells in parallel is typically avoided in more conventional chemistries, but I guess the BMS handles the unequal charge/discharge issues. I wonder if the Earthx & other brands are configured the same way...

Charlie
 
It's designed for reliability in the event of a single cell failure. Full voltage is 14.6V; if one cell where to fail, it would still provide 13.8. Compare that to a standard LA battery where if a cell reverses, or sulphates to the case, the battery becomes a load, not a source.

As for the "ion" labeling, it's just a marketing thing and has nothing to affect the battery operation; I wouldn't pay it much mind.
 
?????

I just called the battery company (Lithium Battery Co) about their LBC-20 and the gent I talked to said it was NOT to be used as a cranking battery...it could ruin it.

Had someone do that and it came back as a return.

Supposedly, it's to be used more as a low drain "storage" battery. When I mentioned this thread and that someone is using it as a starting battery...he said he was surprised about that and was going to have to talk to someone else in the company and get more info. Did not back off the statement that it wasn't to be used in a high load situation like starting, however.

When I find out more info (tomorrow) I'll post an update....
 
Bob, that's quite a stretch. There was a homebuilt (T-18, IIRC) that crashed in the general vicinity of OSH a number of years ago. It had a wing failure. It had been flying for years with rivets in some critical locations where the plans called for AN bolts. The rivets worked just fine as bolts. Until they didn't.

There are lots of times a product will work just fine in an unintended application; I'll agree to that. Most of the 'no name' SLA batteries that some of us use for starting batteries are not intended for that duty, but they do work just fine. But using anything outside its design parameters is...an experiment. The poop sheet on that battery explicitly states that maximum draw should be less than 40 amps, and max continuous should be less than 20 amps. So it might work just fine forever. Or it might work just fine until it doesn't, in spectacular fashion. Until a lot of them have done starting duty in all conditions (hot, cold, overcharged, undercharged, balky engine, etc etc) it's an unknown. Lithium tech is a quite different animal from lead-acid tech, and it's still new to us, using it the way we do.

Charlie
 
When that data sheet says max discharge rate is 40amps, and it also says "short circuit protection", one could conclude that when used as a starter battery, the protection system should think of this event as a short circuit and shut it down, but apparently it doesn't. Hmmm

Bevan
 
LiFePo and Pmags

I'd not seen this thread until today - just been having a read through and comparing with my own experiences.

I Fitted a LiFePo battery to my Pitts in 2013. (The Pitts is IO 0-360 / Injected with 2 Pmags.)

4 Years later I have had Zero issues - other than the reason for this post.

Right from the outset, I had some starting difficulties in cold weather. After much head scratching and battery changing it turned out that I was getting a voltage drop when cranking that made the P mags see less than 9 volts. If this happens they re boot and wont spark until they have seen a full rotation. With the LiFePo4 battery the engine would still crank at acceptable speed, but the voltage dropped over the compressions.

Once the problem was identified I have used a work around solution of a small dedicated battery to the Pmags. 4 years later and all still works well.

I remain a fan of the battery technology - It's the cheapest way of reducing aircraft weight out there (other than going on a diet perhaps). Just thought I'd mention the voltage drop experience in case anyone else has a similar issues.
 
120A no problem

I've done test discharges to verify cold cranking amps of this battery with battery tester. Simulating an engine start (which is 100A on my little engines 1200W starter), I did 120A for 15 seconds no problem. I allowed the battery to rest for 30 seconds and it did it again, three times. Voltage was still >14.4VDC without charging.

I love a good experiment.

I'll continue to evaluate it and report back.
 
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Another vendor is this one:
Next Gen Battery

I spoke with these folks as well and they say 100A is rated peak discharge for 30 seconds, which is the definition of cold cranking amps.
 
I'm talking about the one Ron is using...By The Lithium Battery company.

And, I'm just relaying what the folks answering the phone told me.....

I just got a phone call back from Ron at "The Lithium Battery Company" on the use discussed in this thread for their LBC-20 battery.

Not designed for this type of service, and it is not a suggested or authorized use, just like the conversation with them yesterday.

There will be no support or warranty given...With any kind of problem, you will be completely on your own...

Still looking for one that will fit in the Van's battery box that holds the PC-680 but not the EarthX.
 
But using anything outside its design parameters is...an experiment. The poop sheet on that battery explicitly states that maximum draw should be less than 40 amps, and max continuous should be less than 20 amps.

If you're talking about the Shorai battery, it's CCA is 270amps - well over the max pull from the starter at about 200amps. Continuous approaches zero while the alternator is operating, and my electrical analysis spreadsheet shows a 12amp draw in the event of alternator failure.

>500 hours of operating in MN summers (>90?F), winter (<0?F), VFR/IFR, Day/Night, acro (incl. IAC and mock aerial combat) and zero failures. A complete discharge due to leaving the master on. It's still going strong...
 
I just got a phone call back from Ron at "The Lithium Battery Company" on the use discussed in this thread for their LBC-20 battery.
Not designed for this type of service, and it is not a suggested or authorized use, just like the conversation with them yesterday.

Did Ron explain why?

Common sense says they're not giving up the whole cranking battery market without good reason.
 
When that data sheet says max discharge rate is 40amps, and it also says "short circuit protection", one could conclude that when used as a starter battery, the protection system should think of this event as a short circuit and shut it down, but apparently it doesn't. Hmmm

Bevan

Unless they mean 40 amps per cell, with 4 cells in parallel which would give 160 amps - but it's certainly not stated that way.
 
Love these batteries!!!

...Over 6.5 years, and 1000 plus hrs. with lots of abuse. No issues to date.
I am very happy with the Shorai battery and saved 23 lb over the 925 I removed. Thanks, Allan:D
 
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