Let's find the oldest LiFEP04 battery on the forum. How long have you had your LiFEP04 batteries and how many cycles have they done?

[Z100]

I was thinking of people in the kalahari and Karoo .. those batteries must age quicker without temp control 

[Tallies]

2x SolarWize 5.8Kwh 48 V Lithium Ion batteries 

Installed Sept 2021

Both lost 50% capacity within 6 months and 140+ cycles  .

[Sidewinder]

1 hour ago, Tallies said:

2x SolarWize 5.8Kwh 48 V Lithium Ion batteries 

Installed Sept 2021

Both lost 50% capacity within 6 months and 140+ cycles  .

Eina! 

[zsde]

1 hour ago, Tallies said:

2x SolarWize 5.8Kwh 48 V Lithium Ion batteries 

Installed Sept 2021

Both lost 50% capacity within 6 months and 140+ cycles  .

Thats terrible. Have you had any comms with the distributers yet?
Their claims to the performance are as per the usual.
 

• Built In BMS
• 7 Year Warranty
• Parallel up to 6 Units
• 12-15 Year Battery Life
• Wall Mountable for easy Installation
• Able to communicate with most leading Inverter Brands

[Nexuss]

2 hours ago, Tallies said:

2x SolarWize 5.8Kwh 48 V Lithium Ion batteries 

Installed Sept 2021

Both lost 50% capacity within 6 months and 140+ cycles  .

You probably have some faulty cells and/or BMS issues with that amount of capacity fade over that time-frame. 

[Tallies]

On 2022/03/30 at 4:12 PM, Nexuss said:

You probably have some faulty cells and/or BMS issues with that amount of capacity fade over that time-frame. 

Indeed,had the battery at Potensa who confirmed exactly that ,inferior quality cells or cells from different batches ,pitty the supplier didn't want to honour the warranty .

[Tallies]

On 2022/03/30 at 3:40 PM, zsde said:

Thats terrible. Have you had any comms with the distributers yet?
Their claims to the performance are as per the usual.
 

• Built In BMS
• 7 Year Warranty
• Parallel up to 6 Units
• 12-15 Year Battery Life
• Wall Mountable for easy Installation
• Able to communicate with most leading Inverter Brands

Jip,got a cold shoulder and blaming my installation for the faulty batteries .

[Nexuss]

15 minutes ago, Tallies said:

Jip,got a cold shoulder and blaming my installation for the faulty batteries .

 I would love to know what about your installation was wrong in their opinion?

[zsde]

4 hours ago, Nexuss said:

 I would love to know what about your installation was wrong in their opinion?

The guarantees and warranties are just ink on paper. You pay for it but ultimately you are at the mercy of those that promise you the world.
The cost of starting a legal case are more than buying just another new battery with more promises, and they know it.
Our joys of accepting the promises of an infant industry

[Froggie]

On 2022/01/10 at 8:10 PM, BGb said:

This post deviates from the topic, however I am interested in how fast the lithium batteries "deteriorate".

My 2 x US3000 pylontech were 2 years old on 7 Jan 2022.  In December  I noticed the SOH = 99% (after 23 months of use) based on data from Goodwe ES 4.6

At the moment DOD while on grid set at 5% to have maximum reserve in case of power failures, which happen frequently in our town.

If above results can be extrapolated in a linear manner I should still have >94% capacity in 10 years time.

 

These guys are doing the longer term testing for us

https://batterytestcentre.com.au/batteries/pylontech-us2000b

[Tallies]

21 hours ago, Nexuss said:

 I would love to know what about your installation was wrong in their opinion?

1)I was suppose to use their installer.

2)I was suppose to use their brand inverter(eventhough the marketing of the battery states clear... works with most inverters).

3)Power cables between inverter and batteries are not equel lengths(My installer used the cables that came with the battery in the box).

 

 

[Bobster.]

On 2022/03/15 at 6:23 PM, Scorp007 said:

If you visit big battery rooms like those using 104 x 200Ah  single cell batteries (220V DC lead acid) you will always find fans to exhaust the fumes, running water in case of a acid spill and an aircon to keep the temp low.

Oh the memories... I once worked for what was then the Department of Posts and Telecommunications. All the exchanges ran on 50V DC, and there was always a setup where by grid entered the exchange, was rectified, charged a massive lead-acid battery bank, which then fed the exchange. And yes, the batteries were in a separate, ventilated room.

There was nothing physically preventing us entering that room, but it was understood that it was not a good idea, and an even worse idea to get caught in there.

[Bobster.]

Just to return to the main topic, there's a twist to this. The BMS. All the figures we get are according to the BMS. My batteries are now on their third BMS. So what has that BMS counted? The 2nd BMS was found to have log entries going back to 2018 - at least 6 months before I bought the system. It's also not the BMS that was put in place at install time. So what had that counted? (It returned SOH of 103% for two years). Even when I had CAN in place, I never got a count of the number of cycles, though I know the BMS logged it.

OK... my situation may not be an every day one, but the perceived state of the batteries is according to some piece of gear they are attached to.

This is why I asked earlier on if there was not some way of getting good figures directly from the cells, without having to interrogate a BMS or inverter.

[JTK]

3 Pylon US3000's

Victron kit: MPPT 150/100, 2x Multiplus3KVA's, GX

12 330w panels in 4 strings

 

Little more than 4 happy years: BMS says battery health 94%. Seems to remember it started at 98% not 100... So lets say 4% lost.

Daily cycle for consumption during night. so that is roughly 1500 cycles down to say 20-40%. This is unless Eskom plays around.. then it goes much lower. And cycles perhaps more as well...

Daily charge to full on Solar as first priority / Eskom second at around mid afternoon...

 

-> Battery has never alarmed or bailed on me. Had the Multiplus' internal trip 3 times on Eskom power returning after power outage. Seems to be spikes. Noting else..  Just works...

 

[Bobster.]

On 2022/04/02 at 12:21 PM, Bobster said:

Just to return to the main topic, there's a twist to this. The BMS. All the figures we get are according to the BMS. My batteries are now on their third BMS. So what has that BMS counted? The 2nd BMS was found to have log entries going back to 2018 - at least 6 months before I bought the system. It's also not the BMS that was put in place at install time. So what had that counted? (It returned SOH of 103% for two years). Even when I had CAN in place, I never got a count of the number of cycles, though I know the BMS logged it.

OK... my situation may not be an every day one, but the perceived state of the batteries is according to some piece of gear they are attached to.

This is why I asked earlier on if there was not some way of getting good figures directly from the cells, without having to interrogate a BMS or inverter.

So I am contending that absent proper, calibrated measuring equipment, the state of your batteries is what some piece of circuitry says it is.

I had a first hand demonstration of this recently.

I have a problem with SOC at the moment. Since CAN communications have been removed and the BMS changed, my inverter and the BMS cannot agree on the SOC of the batteries. They are not even in the same postal zone most of the time.

The BMS currently in place has a row of LEDs that indicate an approximate SOC. 4 LEDs, each one indicates 25%. When the system is charging and (for EG) you have one LED burning steadily and the adjacent LED flashing then the SOC (per the BMS) is somewhere between 26 and 50% (and increasing).

This was the situation when Revov came here earlier this week. Lots of changes were made. When they got here I had the scenario I describe above - BMS reporting somewhere between 26 and 50%. The inverter said 71%. At one point the statement was made that the inverter had to be shut down and rebooted and this would bring it into snychronisation with the BMS. This didn't happen. But a few moments later the LEDs on the BMS changed, and suddenly it was reporting SOC somewhere between 76 and 100% (3 LEDs burning constantly, 1 flashing). I said "what happened there?" One of the technicians, who had a lap top plugged into the BMS says "I did that".

Putting aside why he did it or why he thought it was the appropriate thing to do, it makes the point again: The reported state of your battery is what some bunch of circuitry, possibly running some software, tells you it is.

My problem with the discrepancy between SOC as reported by BMS and inverter persists. What is the actual state of those batteries? Who knows? They are on at least the third BMS since new, so any calculation using number of cycles logged by the BMS is not going to be accurate.

This does not make me happy, but I mention it in the interests of debate. I am not accusing anybody of acting to deceive me or with any sort of sinister attempt, but certainly whatever the BMS reports to you can be manipulated very quickly and easily. I am guessing the same goes for the inverter. Meanwhile the batteries are in the state they are in, but unless you take the red pill AND have the necessary, calibrated measurement tools, you won't know what that true state is.

[P1000]

13 minutes ago, Bobster said:

calibrated measurement tools, you won't know what that true state is.

How do you think you would measure the state of the battery?

The best way to do it is to charge it to full based on voltage and current, assume you have the correct capacity, and keep track of how much energy you extract.

In order to know the correct capacity, you have to deplete them completely. With LiFePO4 the voltage does not correlate very well with state of charge - except for the end-stops.

[Scorp007]

@P1000

Would you say measuring the time under a set constant current and knowing the flat voltage curve from the full charged state up to the point where the voltage falls of the cliff would give you the capacity. Allowing for the actual current that was used as a lower current will give a higher capacity.

[P1000]

1 hour ago, Scorp007 said:

@P1000

Would you say measuring the time under a set constant current and knowing the flat voltage curve from the full charged state up to the point where the voltage falls of the cliff would give you the capacity. Allowing for the actual current that was used as a lower current will give a higher capacity.

It probably would, but you won't gain much, while introducing a lot of variance in the measurement.

[Bobster.]

21 hours ago, P1000 said:

How do you think you would measure the state of the battery?

I don't know. I'm no engineer. This is why I am talking in vague terms.

21 hours ago, P1000 said:

The best way to do it is to charge it to full based on voltage and current, assume you have the correct capacity, and keep track of how much energy you extract.

Thanks. This expands (I think) on something told to me recently, that SOC tracking was good in sunny weather, but would drift if there was a run of overcast days. If the batteries never get to full charge, you can't do this tracking. 

Or maybe you can. As long as the inverter sees a true 100% at one point and can faithfully track energy in and energy out from that point. But even then inefficiency will fool the inverter to a degree because you never get out 100% of what you put into that battery. 
 

21 hours ago, P1000 said:

In order to know the correct capacity, you have to deplete them completely. With LiFePO4 the voltage does not correlate very well with state of charge - except for the end-stops.

Thanks for the information.

[CJE]

I would like to be able to see each cells voltage, Internal resistance, balancing voltage and amps. i You can monitor these parameters you will get a much better picture off what state your batteries are in. Because it all is new  and the public needs to be educated no battery supplier can tell you what these values are, it is then easy to make a statement it is your (consumer or DIY) fault. If you could log these parameter  a lot of battery supplies will be out of business because you will be able to proof that the cells were faulty. I think there is only one battery supplier that is doing it in SA but there software is not available for the consumer. My experience after many years of flying Electric RC Planes up to 60 cc in electrical equivalent. I do not even Know if you could communicate with the BMS  and if these parameter are available on the current BMS systems Installed on the Batteries. The Battery supplier's needs to tell us what you are able to do with the BMS and do you have the option to read some off these parameters. What Do the Supplier's define as a Cycle.

[Antonio de Sa]

16 minutes ago, CJE said:

I would like to be able to see each cells voltage, Internal resistance, balancing voltage and amps. i You can monitor these parameters you will get a much better picture off what state your batteries are in. Because it all is new  and the public needs to be educated no battery supplier can tell you what these values are, it is then easy to make a statement it is your (consumer or DIY) fault. If you could log these parameter  a lot of battery supplies will be out of business because you will be able to proof that the cells were faulty. I think there is only one battery supplier that is doing it in SA but there software is not available for the consumer. My experience after many years of flying Electric RC Planes up to 60 cc in electrical equivalent. I do not even Know if you could communicate with the BMS  and if these parameter are available on the current BMS systems Installed on the Batteries. The Battery supplier's needs to tell us what you are able to do with the BMS and do you have the option to read some off these parameters. What Do the Supplier's define as a Cycle.

@CJE If you can get the Modbus protocol from the BMS that can be done, I managed to get it from my battery BMS OEM, I can get all the info you mention above.

I can clearly see that one of my 16 cell is not performing as well as the rest, contacted the battery OEM they tell me to bring the battery over in order for them to balance it.

That is a pain it means me having to travel +_ 200 Km twice and been without a battery for +_ 2 days. 

Also they are not prepared to lent me a battery while they balance my battery cells.

Check this dashoard.

 

[KevinM]

3 X Pylontech US3000 install between June and December 2019. All "were" running without any notable degradation until 12th April 2022 (last week). No notable degradation at all. 1000+ cycles average.

FYI the three batteries are now all in at the Pylontech repair centre for failed BMS's? I don't want to say anything yet but watch this space! Happened during peek sunshine 12H44, no load shedding, no lightning and using about 6000W. 

2 X Axpert 5000, 3 X Pylontech US3000 system and 21 X 335W Panels (150V). High end type 1 and 2 surge protection on panels and grid.

[De0n19]

On 2022/04/19 at 8:15 PM, KevinM said:

3 X Pylontech US3000 install between June and December 2019. All "were" running without any notable degradation until 12th April 2022 (last week). No notable degradation at all. 1000+ cycles average.

FYI the three batteries are now all in at the Pylontech repair centre for failed BMS's? I don't want to say anything yet but watch this space! Happened during peek sunshine 12H44, no load shedding, no lightning and using about 6000W. 

2 X Axpert 5000, 3 X Pylontech US3000 system and 21 X 335W Panels (150V). High end type 1 and 2 surge protection on 

I think that you may have overloaded the batteries. The 150v max on the pv type inverters can't combine solar with grid power. The axpert king is an exception.  Which means that if a cloud goes over then your 7kw array could produce as little as 700w, the rest must come from the batteries.

[JRJ]

Hi

Is it possible to add more LiFePO4  batteries to an existing bank  - old batteries(2x 10kwh 48V 200ah) are in use since November 2021. I want to add same volt, ah and chemistry to my bank but from a different supplier? I am not using any BMS comms between batteries or between batteries and inverters.

Thanks

[Pierre]

Hi 

Where do I find the battery cycles?

CCGX has no history.

Pylontech US3000 x 4

SOH 96% after 2.5 year of grid.

Thanks