Choosing a new battery

[MikeOH]

10 hours ago, N201MKTurbo said:

No, it was a guy.

https://www.upsbatterycenter.com/blog/columbia-dry-cell-battery/

https://en.wikipedia.org/wiki/National_Carbon_Company

https://www.acs.org/content/dam/acsorg/education/whatischemistry/landmarks/drycellbattery/columbia-dry-cell-battery-historical-resource.pdf

E. M. Jewett was his name.

WHOOSH!!!

[Hank]

Since my battery is on the firewall, lighter would be nice to help offset the aluminum Hartzell 3-blade prop. But I just put in a new Concorde AGX last month, replacing the one installed in Sept. '16, so there will be time for others to post their results before I have to buy another. 

[carusoam]

Hmmmmmm…

a pair of light weight batteries would be great to add to an M20C with a single battery, and single alternator….

Kind of an older Long body solution for flying an M20C in IMC… 

I lost the voltage regulator in VMC in my M20C…. Would have been nice to have an indicator light from the VR, and a spare battery to go the distance…. 

Could be a great STC to write if needed… lots of known Mooney parts and drawings already…

Best regards,

-a-

[Jorge0272]

On 1/8/2023 at 2:30 PM, Ragsf15e said:

I looked at their website, and they sure enough have actual STC (not just tso) paperwork on there now.  The AML includes the Mooney models listed.

how do you think it got approved with the limited number of amp hours it provides compared to the original lead batteries?

A li-ion battery will outlast a lead acid battery under full load. I am in the process of STCing a few right now. They charge quicker, last longer and are MUCH lighter! 

[Jorge0272]

On 1/8/2023 at 2:30 PM, Ragsf15e said:

I looked at their website, and they sure enough have actual STC (not just tso) paperwork on there now.  The AML includes the Mooney models listed.

how do you think it got approved with the limited number of amp hours it provides compared to the original lead batteries?

A li-ion battery will outlast a lead acid battery under full load. I am in the process of STCing a few right now. They charge quicker, last longer and are MUCH lighter! 

[N201MKTurbo]

11 minutes ago, Jorge0272 said:

A li-ion battery will outlast a lead acid battery under full load. I am in the process of STCing a few right now. They charge quicker, last longer and are MUCH lighter! 

How do you know they last longer? do you have 10 years of data on these batteries? Does anybody? They may have failure modes you cannot anticipate.

Being lighter is a good thing sometimes and sometimes not. Some Mooney's use the battery weight for ballast to get the CG right. If you put a lighter battery in you would need to add some lead weights to make up for the batteries.

[Jorge0272]

Sorry, last longer as in amount of minutes under a load, not in how long they will be installed in the aircraft. I do have quite a bit of qual data from a certain manufacturer for their batteries.  Will not say what or who. This is proprietary data, but I can say, the numbers that are out there are pretty much what they say. 

Yes, lightweight sometimes is good and sometimes it is not. 

[vorlon1]

On 1/8/2023 at 3:16 PM, Jim Peace said:

For us C owners I do not think its approved...

https://earthxbatteries.com/list-of-stcs/

I talked to these folks at OskKosh last year about the earlier Mooneys, and at that point they were expecting to see them approved 'any day.' However after checking their website a late last year and finding it still unchanged, I contacted them. This is their reply:

"There are very few older aircraft that had the battery forward of the firewall, the Mooney’s earlier models being one of them.  The FAA believes the LOCATION of the battery somehow makes the charging system different and are requiring us to do a completely new STC and process, of which they are still “thinking” about what would be different.  We have been pushing them for almost a year on this subject matter as we must play by their rules, yet they have not provided any rules yet. That being said, we do not have a time line for you. I am sorry.  MAYBE you could get a Part 337 Field approval by referencing the Mooney M20E-K STC on the books."

So there you have it.

[jetdriven]

On 1/12/2023 at 5:04 PM, Jorge0272 said:

Sorry, last longer as in amount of minutes under a load, not in how long they will be installed in the aircraft. I do have quite a bit of qual data from a certain manufacturer for their batteries.  Will not say what or who. This is proprietary data, but I can say, the numbers that are out there are pretty much what they say. 

Yes, lightweight sometimes is good and sometimes it is not. 

The RG35AXC has 29Ah of capacity. The earthX is half that. 

[ArtVandelay]

The RG35AXC has 29Ah of capacity. The earthX is half that. 

Actually 33Ah.

[Ragsf15e]

1 hour ago, jetdriven said:

The RG35AXC has 29Ah of capacity. The earthX is half that. 

I was wondering the same thing… how does a 15ah battery last longer than a ~30ah battery in an emergency regardless of what chemistry it is?

[Pinecone]

2 hours ago, jetdriven said:

The RG35AXC has 29Ah of capacity. The earthX is half that. 

They are so light, install two.

 

[ArtVandelay]

I was wondering the same thing… how does a 15ah battery last longer than a ~30ah battery in an emergency regardless of what chemistry it is?

It doesn’t, generally draining a lead acid battery below 50% will shorten its life, so they artificially limit it’s useful amp-hours. The devil is in the details.

[Ragsf15e]

12 minutes ago, ArtVandelay said:

It doesn’t, generally draining a lead acid battery below 50% will shorten its life, so they artificially limit it’s useful amp-hours. The devil is in the details.

Yeah I wouldn’t normally drain my battery that much, but if my alternator dies imc, I’m gonna want my 30ah available!