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Those cell specifications need to be compared with reality. Reality wins bud. Properly compressed cells don't expand like the specs indicate.

Because threaded rods are elastic and they didn't expand so there was no incredible increase in pressure. Also the "don't crush them" as the upper limit came from members of this board reaching out to the manufacturer to understand these exact questions. You could probably find the...

The only issue with over pressure is crushing, a cell that is not being crushed when empty (which is when you will compress them) will not be crushed when it's full. Therefore there isn't really risk of over pressure on the high end of a charge cycle. Instead the battery simply doesn't provide...

There is calendar aging data that one seen for really hot cells (40c+). But it's all guesswork as far as I know. Until someone measures cells that have been sitting on a conditioned shelf after a decade we won't really know. People should keep their cells indoors and conditioned, but that's...

Get a dc ampmeter, hit all three lines and you'll see numbers that add up a lot better than 8+10=20. Then learn to stop worrying so much!

A is better, not B. Remember internal resistance is largely inverse of capacity. Hopefully that can explain why A is better in a way that makes sense as you wouldn't do B instead of A just because a battery is smaller. Also those spec sheets IR aren't real. The Eve is a lot lower than that...

Compression is the manufacturer instruction. The only reason why it's unclear is that people won't know or acknowledge results until they really have gone through the 10+ years of use. The off grid garage positions are generally a bit foolish, he doesn't know and his positions aren't...

Voltages on lifepo4 have little meaning and the cells we buy are factory rejects that have different voltage curves, especially at the top. To know for sure you need to set the charger to hold voltage for every cell at 3.4, then watch it during a discharge and charge cycle. That will tell you...

You need a better balancer. I'm running the 15a neey currently, it's not ideal but it works. You need to be able to set it to only balance near the top, say above 3.37 or 3.4 average. You have problems when A) balancer operates at lower voltages and unbalances B) amperage too low so it can't...

Why not? It's a lot of work is why.

Reading some of the above, people like to play with their cells and go through a lot of effort. At a minimum all you need to do is: Get some shelving, probably wooden Take the cells out of the shipping boxes and put the cells on the shelves positive to negative. Attach cell compression using...

I personally used a scale to judge the force on the screws, then repeated that amount of torque. I'm practice you want tight (you can't move cells in the middle) but not crushing. I have 24 long strings compressed like this, there is no cell movement from empty to full. In practice when you...

You'd be better served by getting a balancer that can handle it, then just connecting everything and putting it in use. They have really good active balancers now. And yes what you are doing takes forever. That is why you should generally charge in series first until BMS cutoff with a faster...

Yeah it is not the brand, but the chemistry. Cell compression was always advised. I have 24 cells compressed together and see zero expansion from empty to full. I have my doubts about people who say the cells expand under compression - if they actually have any. Uncompressed cells expand...

I might lower the voltage to use something like the Orion BMS (180S). But for an inverter you're limited to something line a Sandi. Huge transformers. Potentially lots of idle consumption.

I just did my customery alibaba check on cell prices and thought I was looking at a mistake of scam. WOW they have come down a lot. Building a 1MW battery for 70-80k. Wow.

What is different about your address? Appt or something? Try a business address

Yeah we seem to be missing enough information to tell what is happening. Other than the likely, that there is a loose connection. One tool I have is the ability to measure internal resistance. You don't have to just measure cells with it, you can measure across the entire battery, check...

I've never understood the allure of these. Communication isn't important, and for the same price you can get a lot more capacity diy.

They just need to write some software to count the cycles and adjust accordingly to bring it back into balance. If it's 62 to turn off ac coupled solar in the day then they need to run it at 58-59 at night to recover those cycles. If it's only running barely over 60 then it's even easier to...

I just need an inverter that can exploit time of use for a few thousand so it will make economic sense - and we are finally moving in that direction.

Your probably right, the specs say: 2x Programmable CANBUS Interfaces • CAN2.0B (11-bit and 29-bit IDs supported) • Independently operate at different baud rates • Fully customizable message formatting • Field upgradable firmware and settings using either CAN interface • One-click setup for...

For your questions: 1) the rule would be to never have cells at a high state of charge uncompressed, and whatever you do beyond that is fine. I just used an active balancer to balance. Took a few days but worked great. 2) I put a scale in my compression setup to figure or how tight it actually...

Good call to use mechanical air conditioning. The battery spec sheets seem to be ok with 90% humidity, but you'd want to check all your components to use a system like that long term. Better to build an insulated box and air condition it with a simple window unit. I'd use foam board and be sure...

Just make sure your BMS balances at 3.4. I think the only reason to cycle would be to get them to a high enough voltage to balance.

For emergency grid down backup float them at 3.4. it's the most cost effective solution, it's what all the telcoms do etc. There is no need to cycle or do anything else at all.

You can't get them cheap enough anymore? Mine were $90 a cell back in 2020 shipped, looking at the same supplier (basen) they now have them for $110 instead of the $77 I paid. So now it's $150/kWh instead of the $100 before, still much better than $300.

I got 48 of the 280ah cells, one BMS, one amp meter and display. There is no way a server rack can compete cost wise with someone willing to put batteries on a shelf. Diy isn't even much work, I think I spent two evenings including compression. I highly recommend doing it yourself for any...

I can second that call out, my notes are long gone but 3.35-3.37 is about where the cells actually fill and then voltage spikes. The voltage varies slightly per cell so 3.4 is the ultimate safe voltage guaranteed to be past the charging phase.

I've seen videos recently about those specific inverters (I think) having an issue with flickering lights. You'll notice that professional installers don't use them, only hobbyists, and there is always a reason for that, generally support issues. The people with the light issue were being told...

You did exactly what I would have done, except I would have just put the cells into service right away and increased the voltage only every few weeks or good sun days.

You'll probably be a lot happier long run with a more professional inverter. These budget ones are nice for hobbies but not necessarily reliable enough houses with, umm, women. Also unless I missed it there was no generator in the setup. You need one they will automatically come on/off when the...

Mimic your BMS settings, that's where they'll end up anyway. I would do whatever was fastest, preferably skipping top balance all together. The only time you really need to top balance is if you have no BMS, and in that's case match your charging profile.

You have the same BMS options as diy electric cars. I think the orion 2 was top of the line. https://www.orionbms.com/products/orion-bms-standard/ Another one: https://www.evwest.com/catalog/product_info.php?products_id=491

You can get a 20s bms and put some lifepo4 together