HennieJH

My voltage was set correct from day 1 . No overcharging and now after 6 years 2 of my 3 batteries are starting to swell . They were all installed on the same day . The cycles are 884 , 772 , 815 . All com cables was installed between batteries . Even the difference in the cycles tells me this is not a good BMS . There is a hell of a alot of these batteries that start to swell on this forum. The system is connect to Sollarassistant and I could see when the first cell was starting to go out of balance . Supplier has disappeared. What is realy a good make of battery.

Good grieve,
 
Reading all the issues with batteries I am so glad I dumped mine went on grid smiling all the way and final;y I am getting my monies worth.
A lot was attacking me when I indicated that batteries are extremely costly and almost useless COMPARED TO GRID TIED and thanks to all I never knew so many agrees with me.
 
Think about it no extra logic, electronics.  My light backups are from a few 12V gel 7.2A @ R70 when they go I dumped them. I do not worry about heat, Celsius cost cycles over voltage under voltage R140 and I have 7 hours backup.  After a few years I dumped them and thanks to Eskom increases I do not feel the pain.

To all of those underlying my point about batteries not worth it and very expensive and requires a lot of additional junk to try and make it successful I appreciate your support,
Thank you.


Many thanks  to all this article underlines why people should go grid tie and not support the Chinese and buy a lot of expensive problems!!!

@Robbo yep that is super conservative in my eyes. The guys doing the scientific experiments indicate that these batteries can take a beating and you will be able to get through those 6000 cycles. Their studies are done in months though, so I'm not sure how bad the calendar aging factor is... maybe nobody knows because they haven't been around long enough.
But if I take your 2880 cycles, that means 11059kwH produced, which means R2.07 per kwH (22,995 / 11059). Still not bad, since I'm paying more than that currently (+- R2.60), and it's likely to go up 15-20% per year over the next few years. The cash outlay is large, but let's say you are in the fortunate position to have an access bond and some spare cash in it, I would guess at 7.25% prime, it's worth it. You get a warm fuzzy mostly off-grid feeling, you're covered for most load shedding scenarios, and you're utilising your excess solar better.
As suggested by @Tariq I've got to wait for a winter to really get a sense for whether I need an extra battery.

So in my calc I considered a few things:
Yes your batteries can go down to 20% SOC but what are you actually comfortable taking them down to daily? My Pylontechs can go to 5% SOC per the warranty but i also want a little left for safety and surprise loadshedding. So in my ROI calc I used a 20% SOC in my daily cycle and not 5%. This is up to you but realistically you dont want the battery to shut down daily.
Secondly as someone else alluded to, how often will you use the stored capacity? My personal experience is that i cycle my batteries 24 times in a 30 day period (80% of the time). Now this may seem like I'm using the full daily discharge from point 1, but the reality is that there are cloudy patches and so there is some dynamic use of the batteries during the day as well, not just overnight usage.
Finally for my own calc, my usage would get a useful life of nearly 21 years! (6000cycles/24 cycles per month/12months). I hope this will be true but it isnt realistic in my eyes. So I took the shorter of the cycles and the warranty and used 10 years. so 10 years x 24 cycles per month x 12months = 2880 cycles.
Maybe I'm too conservative so take or leave what you need

Having built a LiFePO₄ of my own recently and having investigated many different brands, I would recommend Hubble.  Their price per kW/H is very good and they also have a BMS that can communicate externally.  Dumb LiFePO₄ are not worth it.  Those brands will die off at some point they are only around now because people are hasty to buy batteries.
Why I would take the Hubble over Pylon:
Pylon is way over priced in my opinion. Pylon is using 15s configuration (maybe they've switched to 16s for newer batteries?), whereas the likes of Hubble use 16s.  So your system voltage with Pylon is lower which just means lower efficiency for the inverter, especially at the bottom of the battery.  15s is really not ideal. EDIT: Reasons not to buy Hubble
Lastly having done a LOT of investigation, the general consensus is that age is much more of a factor than cycles with LiFePO₄ (at 80% DoD).  You cannot simply use cycles and say, oh so it'll last 15 years.  That is not accurate.  There is very little data on LiFePO₄ life but the data there is (that isn't by a manufacturer who have an agenda) is that LiFePO₄ can realistically last at most 10 years.  Regardless of the number of cycles you have, at 10 years it is likely you cells will start becoming unreliable (ie. some of them will no longer be able to hold charge).  Of course if you drain you battery 100% every day or many, many cycles, age is less important but let's assume you aren't an idiot.
So in terms of life time, there is no solid no manufacturer data yet because the technology is new, so take "life" of the battery guarantees with a pinch of salt, it is almost certainly a lie and they can back up their claim by saying they ran simulated ageing (which is what they do).  But it isn't reliable data.
Lastly LiFePO₄ ages significantly faster in hot conditions. 25 degrees -> 30 degrees is where you ideally want to keep it.  At 40 degrees you are effectively cutting your cell life in half from 30 degrees and it gets pretty hectic up at 60 degrees (like 2 years).
In closing I also want to advise you to be weary of falling into the trap of calculating savings and assuming you will have no additional expenses.  That is unrealistic expectation.  You will very likely have some kind of problems at some point, most people do.  Most people will come back around and call it "school fees".  I call it ignorance.  You are dealing with a complex electrical and complex chemical reaction system, don't expect it to be fire and forget.

I don't know about other manufacturers, but the cycle counter in my Pylons (US3000B on firmware 2.8) is based on full original capacity cycles.  They see a cycle as 266400 Coulomb (74Ah) irrespective of the battery's SOH.
So for a Pylon the internal cycle counter will reach 6000 after 6667 cycles at 90%DOD, or 7500 cycles at 80%DOD.
 

Hi all
With Eskom going for another 20% increase, I think it's time to revisit battery economics vs using the grid.
My problem is I can't seem to find all the info required. I use these batteries
https://solaradvice.co.za/product/fusion-4-8kwh-block-lithium-ion-battery/
Let's ignore installation costs for ease of calculation. Let's also assume that you have solar panels that you haven't maximised (e.g. you have excess solar that you cannot or do not want to send back into the grid, and that these batteries will be filled with excess "free" solar that would otherwise not be utilised).
R22,995 for 4.8kW / 80% DOD / 6000 cycles.
When the manufacturer says it can do 6000 cycles at 80% DOD, what do they mean? Do they mean 6000 cycles x 3.84kW = 23,040kwh throughput during its lifetime? Or do I need to take degradation into account - I assume a "cycle" is 3.84kW as advertised? 
Because if I can buy R23,040kwh prepaid for R22,995 in today's rands (R0.998 a kwh), that is an absolute steal. I could calculated with interest and eskom projected increases, but ignoring that for simplicity (likely eskom increases will outpace prime lending rate). It would indicate that anyone buying solar panels should size a battery rack to store as much excess power as possible (even oversizing the batteries just extends their life so not a waste to oversize a little?)
Please correct me!
Thanks,
Richard
 
 

Definitely will thanks. I am considering a battery change as this is already the second set of the same battery type. Not shooting it down, just saying. Would be good to change to see if other brands have same type of hassles.

Keep in mind, it was probably the lightning and not the battery brand itself.  Do not get too frustrated by this specific brand because of this.  But def. get your insurance involved to get it replaced.

My experience with these batteries, not worth the time and effort for all the issues you will have. Don't recommend or support the use thereof at all.

Thanks. Found the problem, there was no supply to the system pump, this was the reason the pump didn't pump. Long story.

Thanks. Found the problem, there was no supply to the system pump, this was the reason the pump didn't pump. Long story.

Thanks. Found the problem, there was no supply to the system pump, this was the reason the pump didn't pump. Long story.

I have a system in operation using the same inverter you are considering. Attached is the wiring diagram how it is set up. Please only use the information to get a basic idea how to do it because the system has not been approved yet.