Hi guys,

So my older Pylontech 2.4s (3 out of the 4) and one of my newer 3.5s are starting to have issues. They charge up to 100%, but then once the start discharging they fall off a cliff.

What to do?

Depending on the State of Health the "drop" from 100% downwards are increasing.

I know that Pylontech are also sensitive and needs to be balanced - I do this once a year and it seems to work.

 

Can you provide more details on the "fall off a cliff" and if this only relates to the initial drop or continuously?

What is your charging voltage on these batteries?

 

 

 

  

 

My batteries are easily 5 years old. SOH sitting at 90%. How do I balance the batteries.

The Deye inverter does all the charging so I have no real idea beyond 100% at 53.2V.

I'm not expert but aware of (high) voltage charging problems on Pylontechs.

You can Youtube how to balance the Pylontechs - don't think this will add significant value but always worth the effort.

My Pylontechs charge at 52.5 V - can you check if any of the batteries seem to be swollen? I recommend this is the first thing you need to check  - if this is the case don't even try to balance etc.

 

 

 

5 hours ago, Marius2001 said:

I'm not expert but aware of (high) voltage charging problems on Pylontechs.

You can Youtube how to balance the Pylontechs - don't think this will add significant value but always worth the effort.

My Pylontechs charge at 52.5 V - can you check if any of the batteries seem to be swollen? I recommend this is the first thing you need to check  - if this is the case don't even try to balance etc.

 

 

 

Thanks. I'll be trying to balance tomorrow. I have two battery banks (4x3.5 US3000 + 4x2.4 US2000). According to the Youtube vids I should be OK by balancing each bank whilst disconnected from the inverter and with the Can Bus cables disconnected.

I'll give it a bash and see what happens.

 

I have exactly the same setup as you --  just charging them at a lower voltage.

Total 8x batteries, I monitor voltage per battery / cell level and have more or less same age (maybe also cycles) as your batteries. 

 

 

I dabbled in the balancing act this weekend, got cocky, and managed to shut down most of my second (good) bank of batteries until 18h00 last evening.

Made it through the night on a small supplementary genny (emulating two fully charged batteries via a pair of 52V power supplies).

Let's see what today brings.

 

I am in the same boat. 4x US3000 5 years old. Also have that sudden SOC drop near about 35%. What is concerning though is just before two of the batteries reaches the charge voltage / 100%, the highest cell voltage goes 4.65V. After a few minutes it falls and I have a difference of about 20mv between highest and lowest. For now I have lowered the charge voltage to 51.7V as 52.5 (which I was running from the beginning) let those high cell voltages go to 4.7V. It seems I have some bad cells. Pylontech says warranty is void because there was a time my charge voltage exceeded 54V. Because it is an Axpert inverter, it overshot briefly (54.2) when I once tried to "balance" the cells at 53.2 V which is the voltage they "recommended. 

How easy is it to swap cells between batteries? I can solder and are a diy'er. 

It is concerning to see a lot of swollen / faulty Pylontech batteries on the internet. 

Another question: on the Deye inverters the charge voltage is "fixed" by the BMS at 53.2V. So what will happen if there is cells that are lagging in a few years? Then other cells will overvoltage? Or will the BMS communicate to the inverter to reduce charge? Anyone have such a setup with a Deye and Pylontechs and graphs of the cell voltages? 

I really wouldn't hesitate to pay someone to come sort this out for me on-site.

I see there is a 'new' inverter repair place on Bram Fischer across the road (almost) from Franks Burgers.

For now I seem to have 'rehabilitated' my bank of 4 3.5kw batteries, but I'm still struggling with the bank of 2 2.4kw batteries.

I am completely in the dark re cell voltages.

Pylontech 3.2V 25AH Prismatic Pouch Lifepo4 Price 25AH lifepo4 energy battery cell LFP Lithium Iron Phosphat cellonline buy

I wonder if these cells are legitimate, if so, there may be a good market for refurbishing old pylons

I officially give up. My situation has gone from bad to worse.

Who, in Johannesburg, can I call in to assist?

 

Cellen kan u bij atakale.com kopen

Van pylontech 

On 2024/12/11 at 3:50 PM, John said:

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I wonder if these cells are legitimate, if so, there may be a good market for refurbishing old pylons

Interesting. So the Turkish Lira is about 2:1 to the ZAR... So about R360 per pack... Maybe worth taking the risk...

On 2024/12/16 at 11:14 AM, PaulinNorthcliff said:

Interesting. So the Turkish Lira is about 2:1 to the ZAR... So about R360 per pack... Maybe worth taking the risk...

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