AGM batteries seem to be about the same cold cranking amps as comparable lead/acid batteries. It's the Lithium Iron batteries that can really deliver the amperage.
-Jeff > Sent: Saturday, July 02, 2022 at 10:10 PM > From: "Daniel Branstrom via KRnet" <krnet@list.krnet.org> > To: "Jeff Scott via KRnet" <krnet@list.krnet.org> > Cc: "Daniel Branstrom" <4dan.branst...@gmail.com> > Subject: Re: KRnet> batteries > > Thanks, Jeff. You put things in perspective and in order. > > Is it true that, because of their internal construction, AGM batteries > have lower internal resistance, and that enables them to deliver the > higher amperage for cranking power than other types of lead-acid > batteries? It's been a long while since I read up on them. > > Dan Branstrom > > On 7/2/2022 8:01 PM, Jeff Scott via KRnet wrote: > > I'm seeing a lot of misinformation about batteries being bandied about. > > There are three types of batteries. All have their good and bad points and > > any of the three types can be used with any type of engine. > > > > The most common is the old lead acid batteries. Of course they require a > > vented battery box and sometimes will spill acid, even if they are the > > sealed recombinant batteries. They also must be mounted with the terminals > > up to avoid spillage. > > > > The most popular now for a similar price is the AGM (Absorbed Glass Mat) > > type batteries. The most popular of these is the Odyssey battery, > > specifically the PC-680. They deliver good cranking power similar to the > > lead acid batteries and have as good or better life for a similar weight > > and price. Additionally, they can be mounted in any position with now > > danger of acid spillage. My experience has been that I typically get 7+ > > years of service from these batteries. > > > > The less popular, mainly due to price is the EarthX Lithium Iron batteries. > > Note that these are Lithium Iron, not Lithium Ion. They are not the > > highly flammable mess the Lithium Ion batteries are, but I see that > > incorrectly stated over and over as a criticism. It just ain't so. The > > EsrthX Aviation batteries have a redundant battery cell management systems > > on board now with a warning light to let you know the primary system has > > failed and that the battery is now operating on the backup system. They > > also have a wire that can be hooked ot a warning light on your panel or > > your electronic display to notify you to check the battery. However, in > > the case of a charging system runaway, the battery management system will > > disconnect the cells, so using this type of battery alone in a plane with > > an ignition system that requires a battery may not be the best idea. These > > batteries are also very expensive with starting costs close to $400 per > > battery. The big selling point is that this b at > te > > ry weighs 4# as compared to 14# or more for your typical lead acid or AGM > > battery, and provides almost twice the cranking power as the Odyssey > > battery. Additionally, this battery can also be mounted in any position. > > > > I have used all of these types of batteries in my planes. The EarthX was a > > necessity for the raw amperage available when I had a plane with Emags to > > provide sufficient power for the Emags to fire while cranking on the high > > torque starter. But my choice for most applications seems to be the > > Odyssey battery as I currently have all three of my planes equipped with > > Odyssey PC-680 batteries. > > > > -Jeff Scott > > Arkansas Ozarks > -- > KRnet mailing list > KRnet@list.krnet.org > https://list.krnet.org/mailman/listinfo/krnet > -- KRnet mailing list KRnet@list.krnet.org https://list.krnet.org/mailman/listinfo/krnet
