Failed 2 x Renogy 24v 25Ah Batteries And Their "Hassle Free Warranty"

[IM35461]

I have had two of these powering my septic tank aerator with 800 Watts of Renogy solar panels and a 60 Amp rover controller.

The load is off the load output of the Rover.

I bought these batteries as an upgrade to the EcoWorthy ones and they have been in service for about a year.

Anyway, I check the system about once a month and found the aerator was running on mains (auto switchover if no inverter output).

The rover was saying Activate and each battery had 28 volts but providing no power (tested with their MCB's off).

Putting my old batteries back restored normal operation.

I did note a couple of days earlier it got down to 24f during the night (in the UK) but they have low temperature protection.

Anyway, time to log a case with Renogy and over a month of back and throw they seem to think it was my fault for letting them get too cold and and confused with the operating temperature information label -20c - 50c being in error. According to the Rover logs they failed two days after the cold snap.

Thank you for bringing this matter to our attention, and we appreciate your understanding regarding the operating temperature range of our batteries. We sincerely apologize for any confusion caused by the discrepancy between the specified range of -20°C to 50°C and the label indicating down to -20°C.

We acknowledge the importance of accurate information for our customers, and we are committed to addressing this issue promptly. Your feedback is invaluable, and we will thoroughly review our documentation to ensure clarity regarding temperature specifications on both battery labels and our website.

They also had me waste my time trying to "Activate" them and other excuses.

My two YouTube videos, no falling asleep

I am thinking of cutting them open as it would seem Renogy Warranty is a myth.

Any thoughts please?

 

[seneysolar]

You mention the load is off the load output of the rover? The load on the rover is DC
But then you mention switching to the inverter? AC
What is the load?

 

[Alarchist]

I'm not familiar with the Renogy specs, but I don't understand if you thought they could be used to -20°C, so you used them to -20°C? in the UK? what are they claiming is the working rang?

Either way, the BMS is not fit for purpose if it doesn't have low temperature protection and they claim low temperature operation.

 

[JL Hut]

Sorry you're having problems with renogy.. I can't help you just want to let you know that I think they're warranty is worthless. I bought a solar panels from them and one panel had no voltage with my meter. I pop the plastic cover off the back with my fingers. One of the connections wasn't soldered wire to terminal. Tried to turn it in under warranty. They said I avoided the warranty by taking the cover off of my fingers. Total BS.

 

[IM35461]

You mention the load is off the load output of the rover? The load on the rover is DC
But then you mention switching to the inverter? AC
What is the load?

Hi, the load output feeds a Victron 24v / 250Va inverter which then powers the aerator pump. The load is 1.6 Amps @ 24DC

 

[IM35461]

I'm not familiar with the Renogy specs, but I don't understand if you thought they could be used to -20°C, so you used them to -20°C? in the UK? what are they claiming is the working rang?

Either way, the BMS is not fit for purpose if it doesn't have low temperature protection and they claim low temperature operation.

I have asked them what the correct operating temperature range is (the same operating range information is on most of their batteries).

And it only got down to -4c nowhere near the -20c minimum.

I understand a quality BMS would turn off the output at 32f / 0c to protect the battery and with these batteries being sealed it is difficult to verify.

The full pdf manual for these batteries with specs is at https://store-fhnch.mybigcommerce.com/content/RBT2425LFP/Datasheet.pdf and https://store-fhnch.mybigcommerce.com/content/RBT2425LFP/RBT2425LFP-G1-manual.pdf

 

[IM35461]

Time to cut them open like Will Prowse would

I did it outside in case something nasty happened which it did not.

The BMS used is a jbd-sp10s020 which seems pretty generic and they do a BT module for it.

Only one temperature sensor attached to the side of a cell.

The first battery had a voltage of 18.90 and the other 22.50 Volts.

I applied a 0.5Amp current limit to the first one and it was at 22v in 15mins but still no output and it would not start charging via the BMS.

I see a common thing to try is to unplug the balancing cable and when I plugged it back in a blue LED came on and it would charge via the normal battery terminals.

The second one all I did was unplug and plug in the balance cable and it works again. An easy task if the battery is not sealed in a non vented box.

I have them both on charge and will do a capacity test tomorrow.

So one is paying a premium price for components you can buy at AliExpress and with the same amount of support.

Will I be buying or recommending Renogy to my friends? Guess

 

[IM35461]

An update, I gave the two batteries a nice slow charge and on discharge I got the following capacities (they should be 640Wh).

609.13Wh and 582.79Wh so they are far from dead.

Questions, what would make the jbd-sp10s020 BMS units need to have their balance cables unplugged / plugged back in to get them to accept a charge / work?

Is sealing them in a box a really stupid thing to do?

I have ordered the optional Bluetooth modules from China which I guess should give me more information about their condition (if they work).

 

[JWLV]

With these sealed batteries, they really should put a reset button or shutoff switch on them.

I've only had to contact Renogy once due to an annoying issue with a Rover MPPT charge controller. The voltage on the LCD screen was significantly off by more than a volt compared to my multimeters (I have 3). I doubt there was anything that can fix it unless there is a hidden setting or adjustment that no one knows about. But going back and forth with them asking me to try ridiculous things and then finally telling me that the displayed voltage is not important and that the CPU knows the correct voltage, I just gave up on them. They obviously did not want to honor the warranty or replace the unit.

 

[seneysolar]

FWIW, i have had issues with the factory settings on the Rovers. In my opinion, all of their pre-set battery types are wonky in one way or the other.

For example, i had a guys Rover 60 factory preset for lead acids. If the batteries drained below 11v say overnight, the unit would stop. So the next day when the sun comes out you got nothing, the restart voltage was something like 12.6, but youd never get there because its off and your batteries are drained. Its like they applied inverter thresholds for the scc, made no sense. Renogy tech support says "yes this is correct".... Well nobody wants to start a generator on a sunny day to jump start their scc.
I promptly found my way into the user settings and got it to function like a normal cc.

If i remember correctly, the lithium voltage setting was too high and actually worked better on the gel setting. Its worth looking at.

 

[JRH]

Sorry you're having problems with renogy.. I can't help you just want to let you know that I think they're warranty is worthless. I bought a solar panels from them and one panel had no voltage with my meter. I pop the plastic cover off the back with my fingers. One of the connections wasn't soldered wire to terminal. Tried to turn it in under warranty. They said I avoided the warranty by taking the cover off of my fingers. Total BS.

Did you solider it back….? , if so did that fix it..? ….I have renogy panels…just wondering.

 

[IM35461]

My BT modules arrived from China today and here is a few screen captures. They both don't seem to be set to the same battery capacity and both have two low temp warning (one shows four but that was me testing low temp cut off).

The most common error seems to be cell under and over voltage.

Now I can monitor them I will put them back into service and see how they work.

 

[JL Hut]

Did you solider it back….? , if so did that fix it..? ….I have renogy panels…just wondering.

Yes, I sodded it and it worked, I told them I would never buy from them again... and I never did.. This year I bought 83 panels from Sig. Solar.
Renogy is very short sighted business model. Make your customer unhappy so they buy someware else. They are not the only ones selling solar.

 

[IM35461]

An update, my two batteries seem to be working fine and now with monitoring are better than when they were new.

I did not realise the Rover controller lithium profile does have one option to set the Boost Voltage which I set to 13.8v (x2).

Also since then I have replaced the Rover controller with a Victron one and set the Victron Inverter to offer low voltage shutdown.

So far so good...