Bear with me... 12V Lithium Ion Batteries?!

[JPaTV]

Ok--


Dont call me crazy, but I have an idea. (the famous last words )



We're in a big-time renovation and maintenance overhaul on our coach. Putting all new tires, new house batteries, oil, fuel, cooling service, air filter, blue fire system, TPM system, new cameras, dingy purchase and configuration... we're at the 9s on this.


The thing is, LI batteries are crazy expensive... but what if they werent?


I came across this video on YouTube, because the algorithm knows I'm researching battery configurations, solar upgrades, battery monitoring, etc.


Dirt Cheap Lithium Ion Battery! Cheaper Than Lead Acid. You will love this thing! --

https://www.youtube.com/watch?v=L43bArxyszU

I know that traditionally, 6V deep cycle batteries are the way to go with house batteries. However, the amp hours, and load testing that this dude runs on these used LI hospital backup batteries is just plain impressive. He put a 60+ amp load on two 12V LI batteries for an hour, and they performed flawlessly.


It got me to thinking... $150 bucks for a very expensive and critical systems LI battery... to do 4 of them in place of my 4 6V duracell SLIGC115's could be crazy light, crazy powerful, crazy safe, and crazy efficient.


I want to know if I'm crazy, and see what everyone things. Should I be a guinea pig?


I dont know.... but I'm interested, and I hope it proves to be good discussion.


Thanks!
Justin and Brit

[Unplanned Tourist]

Maybe I will have to see what's available from our local hospital!

[CyrusL]

Will Prowse is amazingly smart. Also, I have lithium batteries in my RV now and would NEVER go back. 6v Lead golf cart batteries are for people who just don't know any better. Yeah, these are my own opinions, but I can back them up.

[Concord]

6v Lead golf cart batteries are for people who just don't know any better.



Or maybe live up north?!? And have to content with below zero? Maybe try not to be so harsh with your judgements...

[JPaTV]

So,



Im continuing to research here. Looks like the batteries I posted about last night are no longer at the $150 mark (which would be awesome) -- but instead, demand has increased them to $280+shipping.


These LifePo4 batteries seem to be a plug and play battery to replace lead acid batteries.
https://www.techdirectclub.com/batte...4-power-block/


I'm considering this here - instead of 4 used 40AH 12v Valence batteries, perhaps a SINGLE LifePo4 battery at 170AH would work?


It seems the charge voltage is right, seems like one should hook right up, and the discharge voltage stays consistent, which should allow access to the amperage for as long as the Valence batteries, and definitely beat out the discharge abilities of the Duracell batteries.


I'm definitely not a master of battery technology, but it seems the math works out.


$899 for a new 170AH battery -- longevity, reliability, performance, safety, weight, etc-- seems like a pretty good deal - especially when 4 Duracell SLIGC115s is gonna run me $600 bucks to begin with, and 4 of the used Valence batteries would run more than a single LifePo4.




Am I missing something here?

[SV K]

I have no experience with that brand or seller, but in general...

Those batteries have the safeguards to protect themselves built into the box. So yes, drop them in, hook them up and they'll power your coach.

Charging them though brings up some hurdles.

Inverter/Charger: Are you upgrading it at this time? If not does it have a Lifep04 setting or can it be upgraded? If not does it have an AGM setting? If so although not perfect this setting should be OK. Check with battery MFR. first.

Alternator: Lifep04's will take every amp your alternator can produce, which can lead to alternator burn-out if not managed. Additionally alternators are generally set up for Lead Acid charging. We use the Balmar614 to provide the correct charge profile as well as derating our alternator to lessen the strain on it. A friend installed a switch on his dash that "turned off" the alternator. Worked fine until he forgot to turn it off.

Solar: Buy a controller that has a Lifep04 setting.

If you are comfortable with some basic wiring you can create your own "system" and then you can buy any cells you want to create exactly the battery you want. Although much depends on the cell price+shipping+control parts.

Personally at that amperage I'd buy a "Drop in"

[JPaTV]

Originally Posted by SV K

I have no experience with that brand or seller, but in general...

Those batteries have the safeguards to protect themselves built into the box. So yes, drop them in, hook them up and they'll power your coach.

Charging them though brings up some hurdles.

Inverter/Charger: Are you upgrading it at this time? If not does it have a Lifep04 setting or can it be upgraded? If not does it have an AGM setting? If so although not perfect this setting should be OK. Check with battery MFR. first.

Alternator: Lifep04's will take every amp your alternator can produce, which can lead to alternator burn-out if not managed. Additionally alternators are generally set up for Lead Acid charging. We use the Balmar614 to provide the correct charge profile as well as derating our alternator to lessen the strain on it. A friend installed a switch on his dash that "turned off" the alternator. Worked fine until he forgot to turn it off.

Solar: Buy a controller that has a Lifep04 setting.

If you are comfortable with some basic wiring you can create your own "system" and then you can buy any cells you want to create exactly the battery you want. Although much depends on the cell price+shipping+control parts.

Personally at that amperage I'd buy a "Drop in"

Hey thanks for your reply!


So, I did some voltage testing the other day--
I'm going to reconfirm this, because I cant remember if I had the batteries engaged on the close-in switch () - But, if the batteries were closed in, the alternator did not send voltage to the house batteries, as verified with my multi-meter. However, I did so much testing that I cant recall. But I'm saying this because, if the alternator isnt charging the house batteries, then that should alleviate that strain.


This does bring into question the strain on my generator- because I am near-certain that the generator does charge the house batteries- and if we are running the generator to have things like AC (and higher load items), then closing in a charger that is going to suck up a lot of juice, could also prove problematic.


These are all very useful points, though. I hadnt omitted the idea of charging this guy-- I was hoping to get some insight on this...


I was under the impression that "drop and play" would imply that the charger could handle this also....




I'll have to look into my charger.


Thanks for your reply!

[SV K]

Your welcome,

Yes, if the alternator is not charging the Lifep04, then there will be no strain on it. If it is does now you can always turn the battery off when driving and let the solar charge it.

The coach generator usually provides AC to the Inverter/Charger or Charger and then it charges the battery with DC current. Your charger won't be putting out more amps to charge a Lifep04, it'll just be putting those amps out for a longer period. So it should not be a problem.

[JPaTV]

Originally Posted by SV K

Your welcome,

Yes, if the alternator is not charging the Lifep04, then there will be no strain on it. If it is does now you can always turn the battery off when driving and let the solar charge it.

The coach generator usually provides AC to the Inverter/Charger or Charger and then it charges the battery with DC current. Your charger won't be putting out more amps to charge a Lifep04, it'll just be putting those amps out for a longer period. So it should not be a problem.

Man,
This is great insight. I am sort of inclined to give this guy a shot. Mainly because it has a BMS built-in, And, in the event I want to add another, it’s plug-and-play in parallel, like other smart batteries.

At this point, I’m pretty committed to not going lead acid, or AGM. Partly because of the weight, and space. But mainly because of efficiency, and total output and duration therein. If this battery can go further into discharge, like the lithium ion Technologies suggested, then, it should be a no brainer to that of lead acid, or AGM.

Do you have any recommendations for batteries that you would use, like you were mentioning?

[twinboat]

Originally Posted by CyrusL

Will Prowse is amazingly smart. Also, I have lithium batteries in my RV now and would NEVER go back. 6v Lead golf cart batteries are for people who just don't know any better. Yeah, these are my own opinions, but I can back them up.

Maybe people who don't plan on keeping the RV for 10 years think that lead acid batteries are fine. You don't want to trade away a few thousand $ in batteries and equipment.

[SV K]

Sent you a PM.

[jcussen]

Originally Posted by JPaTV

Man,
This is great insight. I am sort of inclined to give this guy a shot. Mainly because it has a BMS built-in, And, in the event I want to add another, it’s plug-and-play in parallel, like other smart batteries.

At this point, I’m pretty committed to not going lead acid, or AGM. Partly because of the weight, and space. But mainly because of efficiency, and total output and duration therein. If this battery can go further into discharge, like the lithium ion Technologies suggested, then, it should be a no brainer to that of lead acid, or AGM.

Do you have any recommendations for batteries that you would use, like you were mentioning?

I went with Battleborn's and if you don't want a fancy alternator, you use a dc-dc charger to charge your lithiums off the alternator. It will limit the charge so as not to overload the alternator and supply the correct voltage to bring your lithiums to 100% SOC.
https://www.solar-electric.com/victr...ldY3CMOeuRoZga

[JPaTV]

Originally Posted by twinboat

Maybe people who don't plan on keeping the RV for 10 years think that lead acid batteries are fine. You don't want to trade away a few thousand $ in batteries and equipment.

I tend to agree with this, and I think I would normally be inclined to replace it with whatever is in there normally. However, in this case we are doing more of a complete overhaul of the onboard systems, and we are thinking heavily in investing into certain features. Batteries and tires are at the forefront! Thanks for your reply!

[jcussen]

Originally Posted by twinboat

Maybe people who don't plan on keeping the RV for 10 years think that lead acid batteries are fine. You don't want to trade away a few thousand $ in batteries and equipment.

You are completely right. I am one of those super savvy guys that put $12000 in solar, batteries etc. and decided to downsize and sold my coach for about the same as what I would have got without the upgrades. Good for buyers, bad for sellers.