New 80ah LiFePo on Amazon

[MrNatural22]

Just ran across this 12v 80ah LiFePo battery listing on Amazon this morning. Good price. But is it a deal?

 

[svetz]

Whoa!

That's $362.5/kWh including shipping compared to ~$200/kWh for direct from China (which is about the same as DIY from cells), but from Amazon you're protected by Amazon's guarantee.

Says they have a 5 year warranty. Doesn't say new, but does say over 6000 cycles so that should be new.

Don't see how you can go wrong with this.

 

[MrNatural22]

Yeah the arrival date indicates it is a shipment from China like most but yes buying thru the Amazon deal is more $$ than direct but comforting if issues arise on quality.
Amazons price on the Ruixu is higher than direct also, but again Amazon returns are pretty easy.
Curious if it’s shipped with the Anderson connecter?

 

[svetz]

They had some other photos on amazon, looked like 4 prismatic cells and BMS in the case. It would be cool if the case wasn't glued together.
I was going to do a DIY battery from cells, but with prices like these why have the fuss? There's another thread with a stainless steel case off amazon for $313/kWh. Have to figure if these guys do well, other enterprising soul's will follow suit and prices will drop more - which increases sales, which causes prices to drop, which increases sales... you get the idea.

 

[Russ]

They had some other photos on amazon, looked like 4 prismatic cells and BMS in the case. It would be cool if the case wasn't glued together.
I was going to do a DIY battery from cells, but with prices like these why have the fuss? There's another thread with a stainless steel case off amazon for $313/kWh. Have to figure if these guys do well, other enterprising soul's will follow suit and prices will drop more - which increases sales, which causes prices to drop, which increases sales... you get the idea.

I have no idea how to test a battery other than voltage because I have never had a reason. A car or RV is no big deal and if you don't dry camp in your rv a battery is really no big deal. Go to Walmart and get another one and drop it in. This solar business I have learned is another world entirely when batteries get serious as well as expensive so you had better know your stuff or someone who does. It gets confusing at first for beginners.
I just saw today some software called something like CBD PRO that really test a battery thoroughly with your computer so is this what mean when you say test the cycles etc.. ?

I have also wondered about the 18650 batteries. From what I gather you get a bunch of these and connect them together to total I don't how many amps. Can you tell me how many batteries most people get and what kind then how do you make them?

You said you were going the 18650 route but with prices like these new Lithium batteries you would buy a new one. Which new one would you buy the one discussed in this thread? I would not have thought you could get a lot of bad batteries or false claims on battery performance without them being found out and Black Balled quickly. So I could easily be burned on a battery buying deal. The more I hear and read the more confused and not sure what to buy. Since my use of the solar system is not critical I don't want to pay much. What Lithium would you purchase that is inexpensive this one or another Lithium that is 100 ah. From your other post on this and not just this topic you seem knowledgeable.

I was going to possibly get a 2400 watt all in one which would mean 2 batteries. I don't think Will has an in depth video as far as the process of making 18650 batteries but I think he has one video.
Thanks in advance if you can some of these questions. I appreciate your and other members expertise and help !

 

[svetz]

...I have no idea how to test a battery ...

Voltage can tell you state of charge. You can put a watt meter on it and drain the battery to tell you the actual capacity. You can meter the recharge watts to know the round-trip efficiency of the battery in storing the energy.

But also every battery has an "internal resistance" (IR) and that value gets worse over time. So by measuring it you can know the batteries age or number of potential cycles.

There are devices that will measure it by passing an AC current through it; there was a thread not to long ago where Will said the IR for lithium didn't change much over SoC - so the "resistance" method should work. Here's an article on it (be sure to use a resistor rated for the number of watts). That's the theory anyway. If it passes all the tests it should be okay. As to what real life practical values are... hopefully battery guys here can help you out with that.

Oh, even if the cells are half through their life; the 2nd life community would probably tell you they've still got more cycles than LA and it's a better deal.

...Go to Walmart and get another one and drop it in...

Same thing here. The problem is you're not buying from Walmart, you're possibly buying from Bob's Battery Emporium off the back of a pickup. Walmart won't sell you a used battery as new; you don't know who these guys are. If you bought from BattleBorn, it's like buying from Walmart, except not discounted.

But, Amazon does protect you. I'm getting the idea you're not a gambler!

I have also wondered about the 18650 batteries. From what I gather you get a bunch of these and connect them together to total I don't how many amps. Can you tell me how many batteries most people get and what kind then how do you make them?

I doubt anyone knows hard numbers. I suspect the 18650 crowd is the noisiest, and after all that work putting together all those cells I can see why. Will generally recommends the prismatic cells. No fuss, no muss, no soldering, just need a wrench, some copper pipe, a hammer, and easy as pie. These new batteries are coming out are so cheap it's hardly worth the cost of assembly (but it can be fun to do). I'm starting to think manufacturing costs have gone down allowing for lower cost batteries.

You said you were going the 18650 route but with prices like these new Lithium batteries you would buy a new one.

I said "lithium", not 18650 - they're over priced IMHO (but people get fantastic deals all the time). I built one small battery to get a feel for it with 32700s (you can read about it in the Show & Tell section). I'm not quite ready though, and the way prices fluctuate I'll probably put it off until the last moment. First I have to solve that whole annoying AC battery issue in another thread.

I would not have thought you could get a lot of bad batteries or false claims on battery performance without them being found out and Black Balled quickly.

When a brand gets black-balled, the company changes their name. Also harder to do on alibaba since negative posts can be removed.
I had heard bad things about LiitoKala cells, but they had a great reputation as a manufacturer of battery meters. Then I heard that other companies were re-branding their used no-name cells and selling them as if they were LiitoKala cells. So, when I got LiitoKala cells, I got them from the LiitoKala store within AliExpress, a little more protection. Even then the verbiage was misleading and the lack of a datasheet disturbing. Easy to see why they got a bad rep, but they met my expectations.

So I could easily be burned on a battery buying deal.

From Alibaba yes, from Amazon with a little know-how, probably not. Not that you should expect the 7.5 year warranty.

From your other post on this and not just this topic you seem knowledgeable.

Thanks! I'm pretty good at the theory, but light on actual honest to god real life experience. I'm sure you realize somebody like @robaroni, with years of experience, is worth 10 times anything I say.

I don't think Will has an in depth video as far as the process of making 18650 batteries...

Assembling batteries from individual cells is an adventure. It takes a while to do it properly and it's a bit risky as you can damage a cell by heating it with a soldering iron. With prismatics you can assemble 100 Ah battery in a few minutes. Some folks (like @robaroni) have developed an ingenious system to simplify DIY batteries and shared it on the show & tell page. Some people really enjoy the challenge or just love the smell of melted solder in the morning. Some people just want a battery so they can go do their real passion. Some people want me to stop rambling!

Thanks in advance if you can some of these questions. I appreciate your and other members expertise and help !

You're welcome! The members here are really great about sharing what they know; I've been learning a lot too.

 

[Rider]

I just saw today some software called something like CBD PRO

Can you provide more info? Link? The only thing I can find are drug derivatives.

I have also wondered about the 18650 batteries. From what I gather you get a bunch of these and connect them together to total I don't how many amps. Can you tell me how many batteries most people get and what kind then how do you make them?

This guy has a lot of experience building and testing these.
jehugarcia - YouTube

 

[CheezWiz]

Maybe talking about the CBA? I have one I use in this thread:

New Old Stock 50Ah Power Curves.. These look good?

So I picked up some "used" prismatic cells and ran them through my battery testing rig. Voltage seems a bit low, but they are holding out to 50Ah, except for one cell. Running 1c curves now and they are about the same curve at around 3V. Going to test them at 2C next. 1/2 C ^^^^^

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