New Battery time

[Yetti]

Concorde RG-35AXC Platinum Series

 

Last time I ordered one it was $309 from Sprice   December 2017

This Time $495

I guess 6 years aint bad.   IT will be here Thursday.

[Ragsf15e]

1 hour ago, Yetti said:

Concorde RG-35AXC Platinum Series

 

Last time I ordered one it was $309 from Sprice   December 2017

This Time $495

I guess 6 years aint bad.   IT will be here Thursday.

How did it/you decide it was done, fail capacity check or other?

[Fly Boomer]

5 hours ago, Yetti said:

Concorde RG-35AXC Platinum Series

 

Last time I ordered one it was $309 from Sprice   December 2017

This Time $495

I guess 6 years aint bad.   IT will be here Thursday.

That's a good price.  I just got a pair for a little over $1,300.

[FlyingDude]

Isn't it more convenient now to go with etx-900 li-ion?

[Pinecone]

They are available for certified.

https://earthxbatteries.com/product-category/vehicle/certified-aircraft/

The good news is 7.2 pounds versus 32.

Bad news is 11.7 AH versus 33

So if you lose your alternator, you have 1/3 the battery capacity.  IMO, they should at least double the cells and make a 15 pound, 23 AH battery.  To me, that is a better compromise

 

 

[MikeOH]

11.7 vs. 33 A-hr....NO thanks!

[FlyingDude]

They addressed it here:

https://earthxbatteries.com/our-batteries/lithium-battery-technology/

Interesting Facts About Lithium

A lithium battery can use 100% of its storage capability (measured as Amp-Hour, Ah), while a lead-acid battery typically only uses 30%

So they're equivalent.

[ilovecornfields]

Seems like huge weight savings on a two-battery airplane. Would I have to get an MT prop to keep the CG within limits?

[M20F]

4 minutes ago, FlyingDude said:

So they're equivalent.

New things scare me that is why I fly a tried and true 67.  It’s getting harder to find vacuum tubes but pinched waist Amprex 6922’s sound so good. 

[Yetti]

15 hours ago, FlyingDude said:

Isn't it more convenient now to go with etx-900 li-ion?

Lead Acid Batteries don't have thermal runaways.   If a LiPo battery thermal runaways in the tail cone, I don't believe the plane will survive.  YMMV

[Yetti]

21 hours ago, Ragsf15e said:

How did it/you decide it was done, fail capacity check or other?

Last flight I could kind of tell.   This flight I went over to fuel the plane which is a couple  minute engine run.   Filled the tank.   Then would not restart.    Had I looked up the date, I would have got one before it died.

Edited July 16, 2023 by Yetti

[Hank]

23 hours ago, Yetti said:

This Time $495

I guess 6 years aint bad.   IT will be here Thursday.

 

17 minutes ago, Yetti said:

Then would not restart.    Had I looked up the date, I would have got one before it died.

I'm running around 6-7 years, too. I always write the install date on the top of the battery. The old one went in 8/21/16, and was replaced this December. 

It passes capacity checks at annual, but when starting gets slow, I pull it out.

[A64Pilot]

1 hour ago, FlyingDude said:

They addressed it here:

https://earthxbatteries.com/our-batteries/lithium-battery-technology/

Interesting Facts About Lithium

A lithium battery can use 100% of its storage capability (measured as Amp-Hour, Ah), while a lead-acid battery typically only uses 30%

So they're equivalent.

That’s not quite true.

A 30 AH lead acid battery will deliver 30 AH before it’s dead, all batteries deteriorate over time so we capacity check our batteries yearly, when they only deliver 80% of rated capacity it’s time to replace it. Lithium is hands down better for electric drills etc though, charges faster, smaller, lighter many advantages.

Where lithium does better is it’s ability to be deeply discharged for many cycles before they are worn out, but we don’t cycle our batteries they stay fully charged all the time so that’s not an advantage for us.

So far as thermal runaway li-po is susceptible to it, but not LifePo4, and Earth-X is LifePo4.

In my Mooney and I suspect others any weight I lose in battery is likely offset by the ballast I’d need to correct my CG, I’d probably be within limits from the forward CG shift without ballast, but fwd CG slows you down. I fly with 100 lbs in the baggage compt and believe it or not but it’s a little faster with the weight back there.

Now if the battery were firewall mounted then I’d like to lose weight there, so take the Earth-x money and buy a lightweight starter.

Edited July 16, 2023 by A64Pilot

[rickseeman]

On 7/15/2023 at 12:07 PM, Yetti said:

Concorde RG-35AXC Platinum Series

 

Last time I ordered one it was $309 from Sprice   December 2017

This Time $495

I guess 6 years aint bad.   IT will be here Thursday.

Today is a good day to be glad you don't have a long body. It's brutal.

[Ragsf15e]

1 hour ago, FlyingDude said:

They addressed it here:

https://earthxbatteries.com/our-batteries/lithium-battery-technology/

Interesting Facts About Lithium

A lithium battery can use 100% of its storage capability (measured as Amp-Hour, Ah), while a lead-acid battery typically only uses 30%

So they're equivalent.

Both can use ~100% of their capacity, so 30ah vs 12ah in the case of your alternator failing.  The LiPo can do that without hurting the battery, whereas it’s not great for our lead batteries to fully discharge all the time.  Luckily, they remain fully charged and ready most of their life.

[EricJ]

1 hour ago, FlyingDude said:

They addressed it here:

https://earthxbatteries.com/our-batteries/lithium-battery-technology/

Interesting Facts About Lithium

A lithium battery can use 100% of its storage capability (measured as Amp-Hour, Ah), while a lead-acid battery typically only uses 30%

So they're equivalent.

Capacity tests for batteries like Concordes actually test the battery to it's capacity.   The Concorde CMM says to discharge the fully-charged battery at the capacity rate, i.e., 33A for a 33Ah battery, and measure the time it takes to drop to 10V (for a 12V battery).    If it takes more than 54 minutes, the battery is at or better than 90% capacity.    You can keep discharging it from there and get more current and useful power, but it isn't great for the battery and if it goes too low it'll be difficult or impossible to recharge.

Lithium batteries have their places, but GA doesn't seem to be one of them just yet.    Some people are using them in experimental airplanes and living with the tradeoffs.

When I was racing actively a lot of people were trying Li batteries, because they're a lot lighter, which can make a big difference, and theoretically you only needed enough capacity to start the car a few times.   Many people switched back to heavier, higher-capacity batteries after a while.   When you need the extra capacity you really need it and if it's not there when you need it it hurts.   

[rickseeman]

When I looked at lithium for a Bonanza they were $8,500. And a long body takes 2. Wouldn't work anyway on a long body because of w&b.

[exM20K]

2 minutes ago, rickseeman said:

When I looked at lithium for a Bonanza they were $8,500. And a long body takes 2. Wouldn't work anyway on a long body because of w&b.

Sure it would: Just throw a Kelly Aerospace air conditioner in the back.  very little weight or CG change.

[ilovecornfields]

2 hours ago, Yetti said:

Lead Acid Batteries don't have thermal runaways.   If a LiPo battery thermal runaways in the tail cone, I don't believe the plane will survive.  YMMV

Well, it’s right next to the oxygen tank so you don’t have to bother looking for a place to land.

[Jerry 5TJ]

14 minutes ago, ilovecornfields said:

Well, it’s right next to the oxygen tank so you don’t have to bother looking for a place to land.

Maybe you could attach a parachute to the oxygen tank so when it blows itself out the fuselage it drags out the chute.  I hear that a chute is popular. 

[FlyingDude]

1 hour ago, EricJ said:

and measure the time it takes to drop to 10V (for a 12V battery).   

Agreed, but how many of your devices truly work at 10V input voltage? Or 11V? Or even 12.0V even?  I think that's precisely what they mean when they say that you get 30% out of a lead acid battery because the voltage drops as the battery discharges and once the voltage drops to 11V, my gns430W for example would shut down (didn't check the other loads). Some loads have their own backup batteries. In the 430 troubleshooting manual, they even mention raising the voltage >12V if the device complains about low voltage. So yea, Concorde lead acid can indeed hold 30Ah but you can't really use all of it.

I make battery management ICs, I m not too familiar with their chemistry. I should ask a colleague who specializes in batteries.. 

[FlyingDude]

Google got me this article. Interesting read.

https://www.power-sonic.com/blog/lithium-vs-lead-acid-batteries/

[EricJ]

13 minutes ago, FlyingDude said:

Agreed, but how many of your devices truly work at 10V input voltage? Or 11V? Or even 12.0V even?  I think that's precisely what they mean when they say that you get 30% out of a lead acid battery because the voltage drops as the battery discharges and once the voltage drops to 11V, my gns430W for example would shut down (didn't check the other loads). Some loads have their own backup batteries. In the 430 troubleshooting manual, they even mention raising the voltage >12V if the device complains about low voltage. So yea, Concorde lead acid can indeed hold 30Ah but you can't really use all of it.

I make battery management ICs, I m not too familiar with their chemistry. I should ask a colleague who specializes in batteries.. 

Quite a lot of stuff these days runs on reasonably low voltages internally, e.g., 5V, so as long as the power supply can regulate that part of it will keep working.   Some transmitters and such may need more, but I've been surprised how low a lot of stuff will continue to run.   It just depends on how it was engineered.

[FlyingDude]

15 minutes ago, EricJ said:

Quite a lot of stuff these days runs on reasonably low voltages internally, e.g., 5V,

Microcontrollers and Fpgas run at 3.3V and 0.9V core voltages but that doesn't mean the unit will run at lower than rated voltages. 

[rickseeman]

1 hour ago, exM20K said:

Sure it would: Just throw a Kelly Aerospace air conditioner in the back.  very little weight or CG change.

I already have A/C and I'm W&B challenged. I need a MT but I guess I'm a CB. There's nothing really wrong with my CG. I can have only 2 people up front and no problem but people say they handle and land better with an aft CG. (I'm probably using CG as an excuse for wanting a MT because I think they're sexy.)