Solis inverter suddenly not charging battery fully at night

[amadablam]

Hi all


I have recently installed a solis hybrid inverter, two dyness batteries dl5 giving me over 10kw of storage

I am in self use mode with charge current and discharge currentl set at .05 A by installer.

My charge tarriff lowest period is 2-6 am which is when I have charging set. It duscharges after this and supplements pv and then grid. This has been working well and the batteries have comfortably fully charged during the time period

Up until two nights ago everything was perfect. I've made no changes to the set up and stay in self use mode.

Also the charging profile in the graph had been a consistent box shape on the graph but this changed also.

At night there are no extra loads on the inverter.

Each morning the graph is showing the batteries have not charged and are at 60% or so.

I haven't changed anything in the Solis cloud app. I'm wracking my brain wondering what could have changed.

Could it be the cold is affecting the battery charge or something?

Or is there an area of self use section or cloud app that could be causing it

If I had changed a setting it would be easier to locate but this has me totally perplexed.

Has any one come across this sudden change of charging and discharging.

This all new to me and I'm enjoying learning so any guidance would be great.

Setup is Solis inverter and two dyness DL5.0C batteries.

Performance has been excellent but the sudden change in performance is perplexing.

I have attached some screenshots of they might help explain it better. First box shape is normal charge. The next one is what I have seen for two days.

Thanks in advance for the help and for your time.

 

[rpdom]

Cold could be affecting the battery charge. Most batteries will charge slowly at under 10°C and won't charge under 0°C.

One thing you can check on the cloud graphs is the BMS Battery Current. That shows the maximum charge current the battery is allowing.

 

[amadablam]

Cold could be affecting the battery charge. Most batteries will charge slowly at under 10°C and won't charge under 0°C.

One thing you can check on the cloud graphs is the BMS Battery Current. That shows the maximum charge current the battery is allowing.

Thanks so much as we have hit a sudden cold spot that has coincided with this behaviour. So great info thank you!

I will be able to check the bms on the inverter in the morning to check as I didn't see the info on the solis cloud app.

Just out of curiosity according to the app the Max. grid power when Force charging is
Range: 300W~5000W

My installer set it at 300w is this a bit low?

I just thought it seems really low.

Thanks so much

 

[rpdom]

It's a bit low, but you probably don't want it very high. Force charge is used when the batteries drop to the Force Charge SOC level and need a small top up to keep the inverter running. Charging them slowly when they are that low may extend battery life, and they only need a few % charge anyway. However I think mine is set to 3000W. Maybe I should drop that a bit.

 

[amadablam]

It's a bit low, but you probably don't want it very high. Force charge is used when the batteries drop to the Force Charge SOC level and need a small top up to keep the inverter running. Charging them slowly when they are that low may extend battery life, and they only need a few % charge anyway. However I think mine is set to 3000W. Maybe I should drop that a bit.

Thanks very much for. I'm learning a bit a bit at a time. Just when I think it's settled, something like an unpredicted weather change arrives :D

 

[SeaGal]

Hi... not much really to add to @rpdom's reply, but just to confirm I'm 99% certain it will be cold, unless your Dyness batteries are warm and cosy. It seems that Dyness restrict charge to 20A below 15 degrees and, I'll assume, less below 10 degrees.

Every year I answer several questions about Solis inverters not charging batteries. Only last week I was replying to someone else about Dyness batteries - see my posting (linked below), that also includes further links to solutions (such as insulation of the battery and/or heaters).

For battery longevity and performance it is really best to keep them above 15 degrees C and preferably in the 20 to 25 degree C range year round.

You mention an "installer" rather than it being a DIY installation. It annoys me no end that these so called "installers" seem to ignore manufacturers recommendation for installation location to ensure that the battery pack is kept at least at 15 degrees C

Post in thread 'Solis inverter with Dyness batteries'

Dec 31, 2024

same problem today, it keeps setting charging limit to 20amps and never went above 1.12kw until it becomes 48% than it start charging 100amps

My best guess is that the Dyness battery is (by design) restricting charge to 20A when the temp is below 15 degC. That could explain the sudden increase from 20A to the full 100A once the cells got warm enough after a period of low current charging.

To determine if that is the issue, suggest you liaise with Dyness to find out what their temp/charge rate mappings are and/or warm the battery environment and test again.

See also these...

• SeaGal

• 

 

[jgh]

One wonders if Dyness use a different electrolyte chemistry to most. 15 C seems unusually high, as a lower limit.

 

[SeaGal]

One wonders if Dyness use a different electrolyte chemistry to most. 15 C seems unusually high, as a lower limit.

Not at all. LFP should ideally be 20-25C. FoxESS also restrict charging at 15C. Here is the recommended charge rate for EVE LF280K's... other LiFePO4's should be about the same.

See also my posting here

Science based discussion on charging LiFePO4 below 32°F

I am not sure if any BMS has more than 2 states, on and off. Besides… Isn’t this what charge controllers are designed to do (scale current): I am not sure I would want a more complex BMS as it would likely reduce reliability. And for the last line of defence, BMSs need more reliability if...

diysolarforum.com

 

[jgh]

Pylontech's don't seem to start ramping down until about 4 C.
On thinking more, they seem to be limiting to something like a 0.5C rate above that, rather than 1C

 

[SeaGal]

It should be based on temperature and SOC, but yes, should ultimately not exceed cell manufactures C rates. I guess some manufacturers will be more conservative than others.

 

[localhost]

read my post, had some issues with solis and two dyness:

L

Thread 'Solis inverter with Dyness batteries'

Dec 29, 2024

I installed Solis inverter (6kw s5-eh1p6k-l) with 2* 5.0c Dyness batteries and I have two main issue and I was wondering if anyone experienced the same.

The first problem is, the battery charging limits sometimes drops to 20amps, limiting the charging power to around 1.12kw total to charge both batteries, first I thought there is no enough solar input but there is, when I turn something in my house on, the power from solar increase to 2kwh, and once I turn it off, it drops to 1.12kwh again, and when I change the charging limit, it reset once I click save, I found online that the battery...

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• Replies: 19
• Forum: Hybrid and Grid-tie Inverters

I think it is the cold