AGM vs Lithium

[Cosmo]

Comparing AGM with Lithium. I am not an expert. Other views and corrections ar welcome

This is a general NON expert comparison of an VMAX 85 amp hour (510 useable watts) AGM Battery $240 weighing 55 pounds https://amzn.to/2VyOWOK
Battle Born Lithium 50 amp hour (600 useable watts) battery weighing 18 pounds $575 https://amzn.to/2To0t0K

Lithium delivers the equivalent watts at double the cost 1/3 the weight and often half the space. Want to cut costs? Build your own 20ah 12.6v battery pack.! https://www.youtube.com/watch?v=NGp7cGBYOLc

The AGM while rated at 85 amps will deliver 42.5 amps of usable power if your are drawing (42.5 watts an hour or 3.54 amps an hour). Draw more and the battery will deliver less amps. These ratings are often tested at temps of 85F. Vary the temp down and you will get less power. Lead acid has been around from the start of batteries. If you treat it right its a faithful partner. Let is sulfate, leave it uncharged for long period of time, drain it below 10 or 10.5 volts and it wont perform well and you may possibly damage it. Most if not all are familiar with the performance.

ILithiums are in use in use where space and weight are critical such as aircraft, electric cars, electric bikes, electric skate boards, electric scooters. electric motorcycles, high power flashlights and of course portable power stations like Jackery. Most larger lithium batteries being built are using using 18650 batteries right now. There are 7,104 18650 batteries in a Tesla

They are very good at those applications. The king of lithium's today from which most larger batteries are made are the 18650 This is the battery builders dream battery from Tesla to the basement experimenter to your Anker portable battery pack for charging your phone and yes Jackery too.
Putting a large array of batteries together introduces all sorts of technical issues. But they have been solved with electronics. Check the balancing video for an idea of what to consider iwhen shopping for lithium packs especially from no name companies. 18650 NMC Nickle Magnesium Cobalt seems to be a leader at this point. It does not take much for a home builder to get started with Lithium battery packs.

Intro to 18650 Batteries https://www.youtube.com/watch?v=ZQNHyGkhJww
Balancing cells https://youtu.be/fEVQ_8DUpm4
Tesla balancing https://www.youtube.com/watch?v=JiKPjTUfY7U
https://www.youtube.com/watch?v=-a8061yFpRw
https://batteryuniversity.com/learn/art ... ithium_ion

=Cosmo

[GPW]

JMHO, We as yet cannot trust a cell that uses a flammable electrolyte !!! Many New and SAFER batteries are being developed with non-flammable materials …. I’ll wait !!!
In the past I’ve personally had two Lithium batteries explode and catch fire !!! And it is Intense !!!

[John61CT]

Amps are instantaneous current, Ah is energy stored or used over time.

LFP is one specific chemistry, and is perfectly safe, at least as safe as lead batteries.

It is true that most other LI chemistries, as used in EVs, screen gadgets, are too unsafe for use as House banks in or near a mobile living space. NMC is an example, avoid for this use case.

However, using a "drop-in" like the Battle Borns is not the way I'd go. Nor fiddling with 18650s, few of which are LFP anyway.

Also to get a fair comparison, the lead side should be a high quality true deep cycle unit, not mass-market big box, automotive or sold online.

Top quality AGM made in North America:
Lifeline
Northstar, and
Odyssey

You are always better off buying locally if possible, lead is just too heavy shipping costs must be eliminated AMAP.

Call the manufacturers and ask for sources nearby, good deep cycle batts are rarely sold through consumer retail channels.

But unless you really **need** AGM, FLA is even better value

Rolls/Surette, Trojan, Deka/EPM, U.S. Battery, Crown and Superior all making fine examples.

The best battery value by far is Duracell (actually Deka/East Penn) FLA deep cycle golf cart batteries, 2x6V, around $200 per 200+AH @12V pair from BatteriesPlus or Sam's Club. Deka labeled same batts also sold at Lowes.

[Cosmo]

Thanks John

LiFePO4 sounds Great! Safe, cheaper, lighter, longer lasting and more capacity than led acid and way longer battery life (more recharge discharge cycles)!
On top of that it is a possible project for the home builder.
Here is more about building a lithium iron phosphate battery in an hour. Im having trouble finding a reason why I should not try building one.
The profit margin on the commercial batteries appears pretty hefty! 100% to 300% more compared to the home builder!
https://www.youtube.com/watch?v=O94aEaa6d1A

[tony.latham]

We as yet cannot trust a cell that uses a flammable...

Hey, GPW: Don't you have one in your pocket right now? Or nearby?

I toyed briefly with a lithium battery last fall for Burning Woman. In the end, I went with a VMAX AGM. It'll last six to eight years and by then, flux capacitors should be available at a reasonable cost on Banggood.





But I'm watching this thread. Those DIY batteries are intriguing.

Tony

[bdosborn]

I'd be careful with videos from Will Prowse, he often gives incorrect information and most of his wiring/construction technique is truly janky. That being said, he inspired me to build a battery as I figured *anyone* could do it if a hack like Will could. ;-) This guy has much better information if you want to build your own LiFePO4 battery:

http://nordkyndesign.com/assembling-a-lithium-iron-phosphate-marine-house-bank/

The only difficult thing to figure out is what kind of a BMS to use. I still haven't found one that I really like that doesn't cost an arm and a leg. I've got another 180 amp-hrs of cells shipping from China to double the capacity in my LiFePO4 battery.
LiFePO4 Build

Bruce
P.S. I'd go AGM or a Battleborn LiFePO4 unless you like to fiddle with electrical stuff. It's pretty easy to trash a LiFePO4 battery if you don't set it up correctly. Battleborn is the darling battery of the big RV guys, but they're pretty spendy. I figure my battery is about a 3rd the cost of Battleborn but I don't have a 10 year warranty.

[Pmullen503]

A lithium battery will have more usable capacity than a lead acid battery because you can discharge them more without harm. They are less sensitive to being at low charge for a time than lead acid too. So compare costs assuming you'll need 50% to 75% more capacity on the lead acid battery.

[Cosmo]

Thanks for the heads up on good info. Much appreciated. I am getting very itchy to try a battery build.

My climate range is too cold (when its not too hot) for me to use it as my main trailer battery.
But as a battery in a box for lots of auxiliary power it looks like a possible solution for me!

i will check my life and fire insurance before any actions are taken.

Tony the red wagon is looking GREAT! Love the tail lights. Is it true red trailers get pulled over and get more tickets than grey? Baw haw haw.

=Cosmo

[bdosborn]

JMHO, We as yet cannot trust a cell that uses a flammable electrolyte !!! Many New and SAFER batteries are being developed with non-flammable materials …. I’ll wait !!!

LiFePO4 is safe, Lithium Cobalt Oxide is the type that explodes and burns:

https://batteryuniversity.com/index.php/learn/article/types_of_lithium_ion

We are putting LiFePO4 and LTO batteries in data centers now.

Bruce

[brianjonesphoto]

Funny how this topic got started today. I was thinking about starting a DIY LiFePo4 thread.

I’ve ordered a trailer to convert, but I’m waiting for delivery and doing lots of planning. I keep going back and forth between 6v flooded cells and LFP. If I roll my own an lfp will cost $200 more than a pair of gc2 batteries. If I were looking at AGM the cost spread would be less.

I’m trying to figure out if it’s worth the extra cost. In general I’m a big fan of lithium batteries. I’ve already build a 36v 10ah lipo battery and charger for my sones electric motorcycle. I learned a ton on that build and a 12v 100ah lfp battery seams really simple. I could even save a bunch on a charge converter by modifying a meanwell led driver to output 14v@30amp for all of $40 instead of spending $200 on a lithium compatible converter.

I my add a solar array at some point and the advantages of lithium are even bigger as the batteries can take a high current charge under full sun.

Has anyone here built a CALB bases battery? Did it meet expectations?

Thanks



Sent from my iPad using Tapatalk

[bdosborn]

Did you see the LiFePO4 build link above?

Bruce

[John61CT]

Yes CALB is great. Also A123, GBS, Winston and Sinopoly.

For maximum quality / longevity that is all I'd consider.

More than no-name crap of course, but less than drop-ins.

Agree about Will P, a bit annoying and no tech expert but he's been learning over the past couple years, lots worse YTers out there.

[GPW]

Tony sez’… “ Hey, GPW: Don't you have one in your pocket right now? Or nearby?”
YES, and I’m constantly aware of where they are , how they’re stored,charge state , and I never put one in my pocket …( a Throwable device)

Call me paranoid , but if you’ve had a Li battery fire , you too would be “CAUTIOUS” … ( I had Two !!) The old wet cell batteries are heavy and not as good for specs, but they‘ve been fairly safe ( unless shorted ) , recyclable , and easily replaced … Cheaper too!! … That’s me …

“ and by then, flux capacitors should be available at a reasonable cost on Banggood. “ … I just hope I’m still around when they become available … hahahaha With all the electric possibilities these days , you know the battery technology race is a Galloping Horse !!! The future is electric … and likely heavily solar ( or something renewable ) … just look how their cells have improved…

[GPW]

And if you consider the development of other devices , ones that convert the archaic “ rotating mass" into a solid state device , even less power will be required … So you won’t need as big a battery , or maybe none at all ??? The children ( future) will enjoy fully equipped travel trailers that are able to run independently off grid , no hookups , yet power all the comforts of Home …
On a TV home show I saw a 32 SEER AC unit , small quiet , and Very EFFICIENT .. ( thinking a small one for a trailer , soon eh ? )

[tony.latham]

Is it true red trailers get pulled over and get more tickets than grey?

Ask me next month after we've put a thousand miles on her...

T