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Future of DIY LiFePO4 looks bleak…

fafrd

Solar Wizard
Joined
Aug 11, 2020
Messages
4,188
I think the trend both with lower and lower cell cost/Wh as well as the arrival of more and more finished LiFePO4 batteries at lower and lower cost means it’s just a matter of time before building your own DIY LuFePO4 batteries from cells is not going to make any sense.

Today, you can purchase a lead-acid battery for about $0.08/Wh raw capacity or $0.16/Wh usable capacity (@ 50% DOD).

So without factoring in cycle life which is a huuuuge factor in LiFePO4’s favor, $0.16/Wh usable represents pretty much a floor in the cost for energy storage (and hence it is not surprising that used Lithium cells from EV’s are priced right around this level).

The aftermarket cells we have bee purchasing from Chinese resellers are a huge crapshoot, and with shipping costs, it’s getting harder and harder to purchase cells that have high likelihood to not be garbage for much under delivered cost of $0.18/Wh raw or $0.20/Wh usable capacity @ 90% DOD.

Signature Solar’s GYLL battery is$1500 for 5.1kWh of usable capacity, or $0.29/Wh (ignoring shipping costs). Shipping to California is $180 bringing total delivered cost up to $0.33/Wh usable delivered.

And the Powerporter battery the was just disclosed is $1700 for 9.0Wh or $0.19/Wh raw or $0.21/Wh usable @ 90% DOD: https://diysolarforum.com/threads/the-new-lithium-battery-which-use-catl-battery-cell.32066/

Shipping on that battery should cost about as much as shipping raw cells from China, but eventually Powerporter or Signaturesolar or another competitor will have US stock and will sell Off-The-Shelf (OTS) LiFePO4 batteries through Amazon with free shipping as we are starting to see with LiFePO4 cell vendors today.

So let’s assume a worst-case shipping cost of $180 like Signature Solar, that brings raw cost up to $0.21/Wh or $0.23/Wh usable @ 90% DOD,

The point I am trying to make is that by this time next year, it’s a near-certainty we’ll be able to purchase completed OTS LiFePO4 batteries through Amazon or eBay at costs of $0.19-0.21/Wh raw or $0.21-0.23/Whusable.

That means that the savings of taking the risk in DIY will be less than 5% to a maximum of 13% and that’s not yet factoring in the cost of BMS, cables, fuses/breakers, and housing, which will add a minimum of $150 or more realistically $200 to the total BOM (meaning another $0.02 to $0.03/Wh, reducing savings to zero).

So it was fun while it lasted, and we should all take some pride in having blazed the trail of LiFePO4 storage for small-scale DIY solar systems, but it’s likely to be a fool’s errand to head down this same path before the next year has passed.

Even compared to the absolute ‘floor’ of going with lead-acid or used EV cells costing $0.16/Wh usable, an off-the-shelf LiFePO battery will likely not involve a premium of more than 30% to 44% (which is so worth it when the over 10x cycle life is factored in, it’s not even funny).

So anyway, those are my two predictions for December 2022:

1: Finished OTS LiFePO4 batteries on Amazon or through other vendors at costs of $0.23/Wh or less delivered.

2: Far less traffic on this Forum (or possibly a renaming to ‘DIY/OTS LiFePO4 Battery Banks’, either explicit or implied ;)).
 
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>Today, you can purchase a lead-acid battery for about $0.08/kWh raw capacity or $0.16/kWh usable capacity (@ 50% DOD).
I think you're thinking 'wh' when you wrote kwh. 8c / kwh would mean my 81kwh battery bank only cost $0.08 * 81kwh = $6.48! :)

My DIY 18650 second hand cell 81kwh battery bank (~9,000cells) that I built myself cost ~$0.24c/wh or $245/kwh including bus, holders, solder, Batrium BMS etc over the last 3 years based on detailed records/spreadsheet I've kept.

Personally, the prices you list above seem a bit low to me but I'll be interested to follow this thread!
 
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That is a very reasonable set of predictions.... In fact, I vaguely remember I had commented on a thread a year or so ago with a similar observation. At the time I don't think I would have predicted the speed of the changes, but the market direction was clear even then. I think I compared it to the old DIY PC craze of many years back. It used to be that you could build a better computer for less by buying components and assembling them yourself.... but now the over-the-counter PC prices almost always beat the DIY prices.

I was thinking about this very recently and one of the market forces that are driving the availability of turnkey batteries is the increasingly expensive and unreliable grid here in the US. The now annual rolling blackouts in CA and last year's ice storm disaster in Texas have made folks a lot more interested in in-home storage. (Sadly, a lot of the problems we are seeing with the grid are preventable, but with the Politics as they are.... they became inevitable.)

Having said that, there is still a lot of space for the DIYer and Solar.... Even with Pre-built batteries and AIO boxes, there are a lot of combinations and design decisions that have to be made....but even that will evolve. We are starting to see 'kits' that sell a collection of components to put together all or part of a system and I predict that trend will continue. I have seen multiple folks on the forum talk favorably about 'kit' products because they know the components will work together. Right now, most of the kits are small and don't really meet the needs of most folks. Furthermore, you can generally do better than the kits if you shop around for the components.... but we will probably see bundles for respectable size systems that start competing with the price of individual components. What I can't predict is what the kits will look like. Will it be kits of the types of components we see today or will the be new classes of components? Eventually, Powerwall type boxes with battery, inverter combined will likely move into the DIY space. (Not just solar generator size, but Whole house size power walls.)

The trend of DIY opportunities being replaced with complete commercial products is not new. In fact, I would even say that for any DIY space that gets big, it is inevitable that over-the-counter solutions will happen.
 
>Today, you can purchase a lead-acid battery for about $0.08/kWh raw capacity or $0.16/kWh usable capacity (@ 50% DOD).
I think you're thinking 'wh' when you wrote kwh. 8c / kwh would mean my 81kwh battery bank only cost $0.08 * 81kwh = $6.48! :)
Thanks for the catch! Would have been nice if there was a ‘global replace’ on this Forum, but that’s probably asking too much. I painstakingly slogged through and corrected all the mistakes…
My DIY 18650 second hand cell 81kwh battery bank (~9,000cells) that I built myself cost ~$0.24c/wh or $245/kwh including bus, holders, solder, Batrium BMS etc over the last 3 years based on detailed records/spreadsheet I've kept.

Personally, the prices you list above seem a bit low to me but I'll be interested to follow this thread!
I hear ‘ya.

Back in ‘pioneer days’, achieving anything under $0.25/Wh with LiFePO4 was an achievement (and a labor of love).

I played the Chinese-reseller Lottery and got pretty lucky. $1400 for 16 cells delivered that all tested over 272Ah, or $0.10/Wh raw, but once I add in the $100 for my BMS, $70 for cables, $30 for fuse, and $50 for 300kgf clamping fixture, I end up at $0.12/Wh raw or $0.13/Wh usable @ 90% (though I suspect I’m only going to be able to use the battery at 80% DOD due some mismatch in IR, meaning $0.15/Wh usable @ 80%),

But I was one of the lucky ones and would not take that risk again. Average out with all the unlucky DIYers including those that went with Michael Caro and got burned, and I’d guess the average cost per Wh is at least double that if the 50/50 chance of getting budget aftermarket cells that actually deliver is factored in.

The current crop of cells showing up at Amazon and being offered by vendors with supposed access directly from EVE is lower risk, but higher cost. That’s why I’m suggesting a cost of $0.18/Wh raw is probably a more realistic (and safer) bet in today’s market.

It’s truly amazing (though understandable) how quickly this market is changing…
 
Demand for batteries continues to rise, couple that with increasing materials cost and inflation? Prices aren’t dropping on ANYTHING any time soon.
That is a global factor and immaterial to my argument. Inflation will hit Lead Acid batteries as well. The point is that building your own LuFePO4 batteries from cells is rapidly becoming a fool’s errand…
 
Yes - I've made the switch to *small* ready to go LifePo4s like this - https://www.amazon.com/LiFePO4-Batt...rds=12v+LifePo4+battery&qid=1638487429&sr=8-3

I've used them for my generator start-up battery and upgraded an old lead-acid 12v based Duracell Powerpack 600 (https://www.bluepacificsolar.com/pi...battery/duracell_powerpack_600_data_sheet.pdf) with one of these precisely because they're cheap and ready to go and they work!

Last year we got an ewheels ew-36 scooter and it has 4 x 12v lead-acids. I'm even thinking of just replacing those with 4 x cheaper LifePo4. I'm still considering a 14s or 16s DIY so I can have 1 BMS... but as you say, prices and availability are just tempting.

Powerwall wise - I'm just too far down the 18650 path and trying to mix the 2 voltage ranges (14s lithium-ion and 16s LifePo4) in 1 battery bank doesn't really add up for me. :)
 
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Let me know when I can buy battery packs off-the-shelf, insulated and heated, with easy maintenance for anywhere near the price I make my own. There will always be room for DIY since it's not just about price: it's about knowing how the system works, being able to fix it when it breaks with spare parts and not having to send it to some factory, being able to expand as you go without potential vendor lock-in, about those special use cases no one else seems to need.
 
Yes - I've made the switch to *small* ready to go LifePo4s like this - https://www.amazon.com/LiFePO4-Batt...rds=12v+LifePo4+battery&qid=1638487429&sr=8-3
$0.28/Wh delivered, raw - yup, I think that is exactly where the market is today…
I've used them for my generator start-up battery and upgraded an old lead-acid 12v based Duracell Powerpack 600 (https://www.bluepacificsolar.com/pi...battery/duracell_powerpack_600_data_sheet.pdf) with one of these.

Powerwall wise - I'm just too far down the 18650 path and trying to mix the 2 voltage ranges (14s lithium-ion and 16s LifePo4) in 1 battery bank doesn't really add up for me. :)
Yeah, a lot of us have projects we’ve already committed to that we’d be foolish not to follow-up on and complete.

My point was we’re entering the phase where committing to new LiFePO4 cell-based projects is already starting to make less and less sense already today and by this time next year, I predict that the continued trend will mean it’s a fool’s errand…
 
Let me know when I can buy battery packs off-the-shelf, insulated and heated, with easy maintenance for anywhere near the price I make my own.
Of course, the sweet-spot of the market will rationalize first and it will take longer for smaller niche markets such as that needed to allow charging in sub-zero temperatures to reach the same level of maturity / OTS offerings…

There will always be room for DIY since it's not just about price: it's about knowing how the system works, being able to fix it when it breaks with spare parts and not having to send it to some factory, being able to expand as you go without potential vendor lock-in, about those special use cases no one else seems to need.
Except, no. By your same logic, we should have a market for DIY Lead Acid batteries today. Hopefully you agree that that would be a fool’s errand ;).

Or the same could be said for DIY power tool battery packs. It’s just a question of maturity, both of the technology as well as the manufacturing volumes behind it.
 
That is a very reasonable set of predictions.... In fact, I vaguely remember I had commented on a thread a year or so ago with a similar observation. At the time I don't think I would have predicted the speed of the changes, but the market direction was clear even then. I think I compared it to the old DIY PC craze of many years back. It used to be that you could build a better computer for less by buying components and assembling them yourself.... but now the over-the-counter PC prices almost always beat the DIY prices.

I was thinking about this very recently and one of the market forces that are driving the availability of turnkey batteries is the increasingly expensive and unreliable grid here in the US. The now annual rolling blackouts in CA and last year's ice storm disaster in Texas have made folks a lot more interested in in-home storage. (Sadly, a lot of the problems we are seeing with the grid are preventable, but with the Politics as they are.... they became inevitable.)

Having said that, there is still a lot of space for the DIYer and Solar.... Even with Pre-built batteries and AIO boxes, there are a lot of combinations and design decisions that have to be made....but even that will evolve. We are starting to see 'kits' that sell a collection of components to put together all or part of a system and I predict that trend will continue. I have seen multiple folks on the forum talk favorably about 'kit' products because they know the components will work together. Right now, most of the kits are small and don't really meet the needs of most folks. Furthermore, you can generally do better than the kits if you shop around for the components.... but we will probably see bundles for respectable size systems that start competing with the price of individual components. What I can't predict is what the kits will look like. Will it be kits of the types of components we see today or will the be new classes of components? Eventually, Powerwall type boxes with battery, inverter combined will likely move into the DIY space. (Not just solar generator size, but Whole house size power walls.)

The trend of DIY opportunities being replaced with complete commercial products is not new. In fact, I would even say that for any DIY space that gets big, it is inevitable that over-the-counter solutions will happen.
Agree with everything you have said.

And the comparison to the PC market is a good one - we’ll be witnessing the phase where the first Dell’s and Gateway’s emerge in the LiFePO4 market over this next year, in my view.

And just as in the PC market where there continues to be a niche DIY market for high-performing gaming PCs, LiFePO4 battery applications which need to deliver performance outside of the mainstream will continue to justify some cell-based DIY (to get back to upnorthandpersonal’s point).

My point is not that the future of DIY with LiFePO4 batteries looks bleak, merely the future of DIY with LiFePO4 cells.

And you are absolutely correct, as integration of DIY LiFePO4 (and other lithium chemistries) matures into cost-competitive OTS batteries, the DIY effort will move up to a higher level, choosing the best combination of battery, SCC, and inverter for your solar power needs…
 
I used to say that my 560Ah of DIY cells (4s2p) would cost $6000 for an equivalent set of Battleborn batteries. But their heated 100Ah 12v battery now has a list price of $899 with a sale price of $820. So now it's less than $5000. That's some progress, but Battleborn is the high water mark for off the shelf LiFePO4.
 
I used to say that my 560Ah of DIY cells (4s2p) would cost $6000 for an equivalent set of Battleborn batteries. But their heated 100Ah 12v battery now has a list price of $899 with a sale price of $820. So now it's less than $5000. That's some progress, but Battleborn is the high water mark for off the shelf LiFePO4.
Wow, so even rationalization of the heated LiFePO4 battery market has begun.

At $820 for 1.275kWh raw or 1.15kWh @ 90% SOC, that’s still a hefty $620 or 310% premium over what 2 12V Lead Acid batteries would cost, but it’s a start and the trend will no doubt continue.

As the much cheaper OTS batteries from China start to reach these shores, it’ll be interesting to see how long Battleborn as well as others like SimpliPhi will be able to maintain their premium pricing.
 
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The point of DIY for me has always been to get a superior system to what is commercially available.

The bar for commercial ready made batteries has been drastically lowered in recent times, making DIY even more attractive.
Would appreciate to understand what ‘bar’ you are referring to.

Are you saying you believe that you can build a DIY LiFePO4 battery with better performance and/or quality than listed batteries such as those offered by outfits like SimpliPhi or Signature Solar (or BYD) or that your DIY battery is going to deliver close to that same level of quality / performance for a much more economical cost?
 
Would appreciate to understand what ‘bar’ you are referring to.

Are you saying you believe that you can build a DIY LiFePO4 battery with better performance and/or quality than listed batteries such as those offered by outfits like SimpliPhi or Signature Solar (or BYD) or that your DIY battery is going to deliver close to that same level of quality / performance for a much more economical cost?

Pre-made “stackable” units using low spec cells and BMS have proven to be problematic over longer term.

Yes, i have consistently demonstrated i can assemble DIY packs that deliver more kwh/$ than commercially available units.

Where i live there is no grid power. Over the course of many years you get to know what works in practice.

Plenty of people think they know better the first time. After their “professional” systems fail inside 5-7 years they realise they might not know it all.

I’m talking 20+ kwh systems only - smaller systems the benefits of DIY aren’t so apparent.
 
I’m new here, and shopped the market high and low for a 200Ah +/- lifepo option with consistent reliability and reputation. The good options are still pricey, the cheap ones cut corners. So I just ordered 230a eve cells from Amy and a Overkill bms and will build one myself.
The knowledge base here lends confidence, and I’ll get exactly what I want with all the whistles and bells for about half of the premium options.

I just don’t think most people are willing to do the research to tackle a DIY option in the first place. And identifying reliable sources and proper components without this forum would be a daunting task at best. I came here thinking ’no way’ and here I am. Thanks guys! Lol

I used to build computers too, now we buy Dell refurbs and fix them if they break. The high end stuff is still high end.

So that’s the humble viewpoint of a raw noob.
 
Pre-made “stackable” units using low spec cells and BMS have proven to be problematic over longer term.
The thread is not about batteries built with ‘low spec’ celll (either OTS or DIY). I specifically mentioned SimpliPhi and BYD, so do you consider those examples of OTS batteries using ‘low spec’ cells that prove ‘problematic’ over longer term?
Yes, i have consistently demonstrated i can assemble DIY packs that deliver more kwh/$ than commercially available units.
OK, my lead post speaks precisely to the cost gap between DIY LiFePO4 and OTS LiFePO4 and the emerging trend pointing to about zero cost differential a year from now.

So on what you’ve achieved in the past (when OTS offerings were few and extremely expensive), not really relevant to the observation I’m making.

If you believe a significant-enough cost differential will exist a year from now and beyond to continue to make DIY LiFePO4 an attractive option, I’m all ears (or rather, eyes ;)).
Where i live there is no grid power. Over the course of many years you get to know what works in practice.
I haven’t factored in anything for the risk a DIYer dirsn’t know what he is doing and screws up - just the crapshoot of purchasing bargain-basement aftermarket cells from China and the ever-diminishing cost differential versus increasing numbers of higher-quality OTS offerings…
Plenty of people think they know better the first time. After their “professional” systems fail inside 5-7 years they realise they might not know it all.
Again, not a factor I’ve even mentioned. If you believe your DIY battery will outperform / outlive professional OTS batteries from the likes of SimpliPhi or BYD, please explain.
I’m talking 20+ kwh systems only - smaller systems the benefits of DIY aren’t so apparent.
I’m speaking mainly to the seeetspot of the market, meaning batteries selling in high-enough volumes through consumer channels to eventually appear on Amazon.

I don’t have an opinion about whether 20+kWh OTS LiFePO4 powerwalls will ever compete on cost against DIY offerings, though that higher-cost, lower-volume market means that if OTS ever does catch up to DIY, it’s gong to take longer than the ~1 year I’m forecasting for batteries in the 5-15kWh range.
 
I’m new here, and shopped the market high and low for a 200Ah +/- lifepo option with consistent reliability and reputation. The good options are still pricey, the cheap ones cut corners. So I just ordered 230a eve cells from Amy and a Overkill bms and will build one myself.
The knowledge base here lends confidence, and I’ll get exactly what I want with all the whistles and bells for about half of the premium options.

I just don’t think most people are willing to do the research to tackle a DIY option in the first place. And identifying reliable sources and proper components without this forum would be a daunting task at best. I came here thinking ’no way’ and here I am. Thanks guys! Lol

I used to build computers too, now we buy Dell refurbs and fix them if they break. The high end stuff is still high end.

So that’s the humble viewpoint of a raw noob.
If I had to purchase a 200Ah LiFePO4 battery today, that’s what I’d be doing as well.

It’s the trend I’m pointing to, and my observation that other noobs following in your footsteps a year from now are likely to increasingly choose an close-to-equivalent-cost OTS LiFePO4 battery option.

Just for a concrete example of the emerging trend I’m speaking to, can I ask what you paid for your 230Ah cells delivered?

One year ago (or even 3 months ago), 280Ah LiFePO4 cells through Amazon like these for 4-for-$606 delivered ($0.17/Wh) were not an option: https://www.amazon.com/Lifepo4-Batt...cphy=9032080&hvtargid=pla-1461073245306&psc=1

From all reports, you’re likely to be getting good-quality cells purchasing from Amy, but having return rights with 2 months to test your cells basically takes the risk of getting screwed out of the equation, so hopefully you’re getting your cells for well less than $150 each all-in.
 
The OP is not saying there is no reason for building your own battery. There are many reasons to do a DIY battery, the price being an important one. He is just pointing out that the trend line in the pre-built batteries is rapidly changing the price part of the build-vs-buy equation.

The prices of quality pre-built LiFePO4 batteries are going down. That is undeniable. For some folks, the current premium for the quality rack-mount batteries is already low enough that they are re-thinking building their own. I would still build my own, but I have to admit that not having to build a battery box, balance the cells, and put it all together is making the current pre-built premium seem almost worth paying. Some folks will gladly go through the effort of building their own battery for the current cost savings (and other reasons), others will make a different choice. Neither is wrong. Everyone has different value sets and objectives.

The point is that the pricing trend indicates there will be more and more people that will opt for pre-built. In fact, we will see more and more people do projects that would not have attempted the project if it entailed building from cells. This growing market will be answered with growing options and dropping prices for pre-built LiFePO4 batteries. Will it be radically different in a year like the OP implies? I certainly don't know, but it is clear the build vs buy equation is changing.

Going back to the PC comparison.... There used to be a lot more sources and options for PC components. As the Dells, HPs, Gatways, etc lowered the price of systems, the consumer market for PC components shrank.... consequently, there are fewer options and higher prices for PC components. If we look forward 5 years.... will the availability and costs of BMSs and Cells change in similar ways? If enough people stop building their own batteries it is a possibility.
 
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