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Does It Really Pay To DIY Lifepo4 Batteries?

Wjm1964

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Feb 4, 2022
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Reason i ask is that while i can perceive some financial savings in building a very large lifepo4 battery bank of over 32 + cells, is it worth it to DIY build anything smaller? When you factor in all the time, knowledge needed, cables, connectors, fuses, the tools needed, Your BMS's, delivery times / costs etc does it make economical sense. Are you better off just buying a decent brand lifepo4 with a warranty?

What's your thoughts. I can understand the self satisfaction of going DIY as you know what you've built but one mistake can be a disaster. Just wondering if people actually do save enough to warrant a DIY

Thanks
 
Worth it for me to do a 2p16s with 280ah.
Saves a little under half of a pre-pack solution.
It will also be insulated, heated and weather tight so it can go outside the house where it belongs.
Inspector probably won't like it so it'll hook up after the string inverters are blessed.
 
Some builds do seem to go a bit overboard on design and assembly. Although they may have access and experience with more machinery than some. Basic wood box or milk crate build can be economical once going over 200 ah.

Yes economy of scale increases the value as the battery gets bigger as there can be more shared components. Also a compact DIY design can save significant space that could be limited.

Also there are plenty of issues posted with "low price" drop in batteries. That warranty is great if the drop in can be exchanged at a local store in 30 minutes and I don't see that happening.

For a newbie with minimal electrical or handyman skills this may not be a good starter project no matter the savings.
 
Reason i ask is that while i can perceive some financial savings in building a very large lifepo4 battery bank of over 32 + cells, is it worth it to DIY build anything smaller? When you factor in all the time, knowledge needed, cables, connectors, fuses, the tools needed, Your BMS's, delivery times / costs etc does it make economical sense. Are you better off just buying a decent brand lifepo4 with a warranty?

What's your thoughts. I can understand the self satisfaction of going DIY as you know what you've built but one mistake can be a disaster. Just wondering if people actually do save enough to warrant a DIY

Thanks
there's really extensive topic on already here :

 
I'm guilty with respect to those "overboard" assemblies, but if you can use a really long lifespan then I feel that they're worthwhile. There's another argument against DIY, however, and that's the tools and accessories you need to buy just once (for any number of packs): An accurate torque wrench with a low range of settings, a bench charger, and so on.

A few frequently bad things with pre-built packs are (1) the worst of them (especially from CN) claim to be "bigger" than you actually get; the internal busbars aren't as good aren't as good as you can make or buy yourself; (3) they sometimes have "mystery" BMS units; and (4) they are never ever compressed for longer lifespan. In addition, over time, cell expansion and contraction can make the busbar-to-terminal connections more loose, and less conductive - that's a bad thing.

Some companies make great pre-built packs (such as battleborn), but their prices tend to be high.
 
Mainly based on your personal opinion. Like most people say, DIY batteries can get you a relatively cheap battery pack and can give you a sense of accomplishment. But the downside is that you have to learn the relevant battery construction knowledge, otherwise you may make your battery die due to some small mistakes. Of course, OTS batteries are fine too but can be relatively expensive, and in case they break, you'll have to return them to your battery supplier for repair. If you are interested, you can read the difference between DIY battery and OTS battery, which is better and which is more worthwhile, it is all up to your own feelings.
 
Why not a hybrid approach? Purchase the cheap, pre-made, Amazon-available Off the Shelf (OTS) batteries and take them apart ala @Will Prowse style? You can then mess with the innards of the cells, BMS, connections, temperature sensors, etc to you liking. Augment the pre-made components with your custom upgrades to make them just as you want and need.
 
I'm building 20kwh for less than some places want for 10kwh. Yes, it takes more of my time (quite a bit more) and more head scratching on my part, but the savings is worth it IMO.

I totally get how time is money to some people though. I have a lot of time constraints, but I have money constraints too, so I'll find the time hah.
 
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Reason i ask is that while i can perceive some financial savings in building a very large lifepo4 battery bank of over 32 + cells, is it worth it to DIY build anything smaller? When you factor in all the time, knowledge needed, cables, connectors, fuses, the tools needed, Your BMS's, delivery times / costs etc does it make economical sense. Are you better off just buying a decent brand lifepo4 with a warranty?

What's your thoughts. I can understand the self satisfaction of going DIY as you know what you've built but one mistake can be a disaster. Just wondering if people actually do save enough to warrant a DIY

Thanks
It’s really a personal / Money thing.

Some like to do it.
Some do it to save money and yes DIY on large batteries is cheaper still yet than server rack batteries.
In the future that may change.
Now that we have a reliable supplier it makes things much easier.

Some don’t want to take on the learning curve, equipment Or time to do it.

Us that have built our own can attest to at least a few years of service and cost savings.

In my opinion DIY batteries are worth it for a couple reason.

A. Knowledge of the system.
B. Price
C. Repairable

Some would rather just buy them and be done.
 
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I am upgrading from agm to lifepo4 and had intensions of building a battery but way the prices for 3.2v prismatic cells are going up and import duty etc for me I can buy batteries here in Australia more suited to my needs that to make one. I only need a 5kw battery . My current system is 24v but may up grade to 48v pending on finances .
 
Reason i ask is that while i can perceive some financial savings in building a very large lifepo4 battery bank of over 32 + cells, is it worth it to DIY build anything smaller? When you factor in all the time, knowledge needed, cables, connectors, fuses, the tools needed, Your BMS's, delivery times / costs etc does it make economical sense. Are you better off just buying a decent brand lifepo4 with a warranty?

What's your thoughts. I can understand the self satisfaction of going DIY as you know what you've built but one mistake can be a disaster. Just wondering if people actually do save enough to warrant a DIY

Thanks

I personally enjoyed building my own packs. The hardest one to build was the first one, but once I got the 'formula', I recorded all the sizes of the plates and such, and producing additional packs was a lot faster.

And later, I can dismantle cells from my 12v system when I am ready to assemble my final 48v house setup, I have a longer set of plates, and is easy to repurpose and put those cells into 48v packs with my other BMSs... My modular design allows for easy repurposing to make whatever voltage I want.

I use a common cell (280Ah EVE-style cell) across all my batteries, so they are easily replaceable if I have a failure. I provide my own warranty service, it's warrantied for life... Sometimes the cell manufacturer could replace a failed cell for me, but if they don't honor it, I can just buy a common cell and throw back in it. Same with BMS...
 
I am upgrading from agm to lifepo4 and had intensions of building a battery but way the prices for 3.2v prismatic cells are going up and import duty etc for me I can buy batteries here in Australia more suited to my needs that to make one. I only need a 5kw battery . My current system is 24v but may up grade to 48v pending on finances .
I am also in Aus. What is your price coming out at? Just finishing my 2nd 5kW pack and would say about US$1000.
 
Was quoted this from gobelpower after their sites states all taxes and freight paid for. The quote is in USD. By the time it lands on the door step it is just over $3500aud
 

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That's 16 pieces so over 14kW. AU$3500 looks alright to me. For 5kW I paid US$722 so add for BMS, balancer and other bits and easily do for a 1000.
 
...... Are you better off just buying a decent brand lifepo4 with a warranty? .....

Thanks
Has ANYONE actually been successful and happy getting warranty service or replacement with a malfunctioning manufactured battery, especially brands from China? I would NOT count on it or include warranty service as part of they buying equation. It is likely to be a headache, hassle, expensive or worse.

I purchased 2 GSL 100 AH batteries and required service on both for different reasons and support was HORRIBLE and I ended up fixing the problems myself via the internet. Their BS and back peddling and disgusting support and then their sudden cut off of communication was a complete reversal of their sales bullshit. Felicity batteries completely lied to me and then again stopped communication when asked to prove their lie. Other Chinese manufacturers when contacted were of similar bullshit. GSL, 18 months ago was the most convincing. Today no way in hell would I expect warranty service and it will likely be an expensive nightmare, especially for a manufactured battery from China. Dealing with GSL from getting info pre-purchase, to the bullshit during purchase, then the bizarre extreme bullshit regarding shipping, idiotic holiday delays, idiotic translation problems through the entire process. Idiotic dealing only with 1 salesperson allowed, Complete useless manual with wrong or poor information and settings. Abysmal support where they never did solve the problems and then stopped communication. They could not or said they could not open jpegs nor mp4 videos, despite my sending them 3 different methods via email or email links or email links for downloads. Very smart tech support could not open the files and yet my friends could.

At least with building from individual cells, I've read and watched videos of DIY'ers getting a few cells replaced under warranty or from user mistakes, but I have yet to read or view a video of a manufactured battery being replaced or repaired in an easy and successful manner, especially if off shore. Maybe Battle Born has better service or one of the US distributors of Chinese batteries, but not everyone lives in the USA, so what about those buyers? And even the US distributors have had hassles as you can read in the forums.

And as mentioned earlier, buying pre-built, you learn very little and the battery manufacturers will teach you very little. Hell some of them have incoherent and totally useless User Guides / Manuals, eg: GSL Energy.

Personally, when or if I have to upgrade my battery, I would build my own, choose my own BMS, have the BMS software for troubleshooting and learn what to do vs. relying on Manufacturers most of which will be hard pressed to provide support let alone service and easy successful warranty service. Most will call you a liar, maybe not up front, but you will have to prove your case first then jump through many hoops. Hell Outback USA support was so convoluted, communication was so poor and lacking and bizarre and warranty service took months, which for someone 100% off grid is a big deal, where Outback with all their knowledge and resources and reputation could not have cared less.

Summary, unless it's local, expect service, support and warranty to be a hassle or non existent. Hell, just read some of the threads of hassles forum users here have had with solar panels, inverters and batteries. The solar business is kind of a joke when it comes to service and warranty. At least it was for me and some others. So go lower cost, learn a lot and you'll probably make as good a battery as the manufacturers.
 
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Diy batteries are simple to build. But you have to stay mindful of the available power at your fingertips. Take your time and double check yourself at every step.
 
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