Renogy / Fogstar not charging

[Frigo110]

Hi,
I had until yesterday a California AGM Battery working together with a Renogy 12V 40A (RCB40D1U-BT2-UK).

I changed the battery for a Fogstar Drift 105Ah and now it doesn´t charge.

The profil is tset correct, the ignition + works, all cables are ok, all my accessories have power...
In the App I can see the leisure battery as well as the starter battery voltage so I assume batteries are connected correct.

Any ideas?

 

[Salty Spuds]

how do you know it isn't charging? what's telling you ?

 

[Frigo110]

The app tells me it’s not charging and after driving for an hour the battery is still at 51% soc

The starter battery is at 12.7V so above the threshold to charge the leisure.

 

[Salty Spuds]

any fuses between the charger and the LB? The old AGM battery would have drawn 15-20A the Fogstar will take all it can get. I wonder if the cali is fused for a less greedy battery.

 

[Frigo110]

Sorry - I don’t have a cali - I just used a battery.
Now it’s starter battery fused to dc/dc - unfused to Fogstar.

 

[Salty Spuds]

Ahh Right! Has the fogstar ever charged since you've had it? I wonder if the BMS needs resetting. Can you get to the battery and disconnect it from the renogy B2B and use a standard (with lithium profile) battery charger? Give it a "Bench" charge before letting it loose on the van?

 

[Salty Spuds]

Page 7 of the manual, Step 3 - Charging and Discharging ButtonsOn the main dashboard of the App, you'll find the'Charging' and 'Discharging' buttons. Toggling these buttons to 'OFF' will turn the chargeand discharge functions of the battery OFF.

Have you enabled charging in the app?

 

[Frigo110]

Charging is enabled. Yes it was charging for a few minutes and then stopped.
I go camping tonight so will have to survive on 50% until I can charge it on a bench.

 

[Salty Spuds]

It's showing 61 cycles. Have you bought it new or second hand?

 

[Frigo110]

It´s a second hand one.

 

[Salty Spuds]

It´s a second hand one.

Hmm! I wonder if it’s faulty. Did you buy it from a known source or random seller?

 

[Frigo110]

I bought it private. I had a look in the app for cell balancing and cycles and it looked good to me.
Could be faulty - I´ll check all connections next week and try the older battery again, that one charged fine.

 

[Salty Spuds]

There’s a BMS reset procedure in the manual, it involves completely discharging the battery, which you might do if you’re off camping.

 

[Frigo110]

Thanks for your help.

I´ll have a look, I can waste some energy to empty it.

 

[Salty Spuds]

Thanks for your help.

I´ll have a look, I can waste some energy to empty it.

Keep us updated for future reference please.

 

[Frigo110]

Keep us updated for future reference please.

Will do.

 

[Frigo110]

Quick update, I have discharged the battery until "low voltage protection" and now charged to 100%.
Cell Voltage deviation is 0.004V w/o load.

I´ll leave it on charge for a bit longer and try my luck next week.