FoxESS Community - Owners & Installers Forum

Hi all,

I've just had an EP11 (with heating) fitted.

The BMS firmware is v1.006, but the "Battery warmup" element in Quick Settings is greyed out (see pic).

The battery details only show the model number as EP11 (see pic). Is it possible that this is not the heated version? There is a "WARM" label on the box, but the specs state no charging below 0C (see pics).

The battery was charging at 0.86 kW at 02:30 last night (when it was reporting a temp of 6C), then ramped to 2.34 kW sometime after 04:00.

My inverter seems to be configured for a max 10A of charging, so perhaps that's why the charging maxxed out at 2.34 kW?

Thanks, Martin

I raised a support ticket from the cloud 2 app, and it seems [edit:] they also needed something doing to the inverter.

The heater config options are now active on the app.

Re the charging rate, I think I now understand that the battery sets the limit dynamically from the cell temps. Not sure why a 9.1C battery is currently limited to 5.5A charging, tho???

I'll bump up the heating overnight & see how quickly I can charge then. (Today is a discharge test.)

cheers, Martin

Hi Martin,

I have the EP11-H too. You're correct that the maximum charge current is set dynamically based on the lowest cell temperature. The thresholds are something like this:

<0ºC: 0 A
0 to 5.9ºC: 2 A
6 to 10.9ºC: 5.5 A
11 to 15ºC: 10 A
15 to 20ºC: 15 A

I haven't found a definitive source for these limits, but have pieced them together from other posts on this forum. Please take with a pinch of salt.

In my opinion the default heating settings aren't that helpful as it only kicks in at 0ºC and then heats up to 10ºC. I have mine set to kick in at 6ºC and heat to 11ºC. I want to avoid dropping into the 2 A current limit as then I can end up in the position of not being able to fully charge the battery on my cheap overnight rates.

Anecdotally, I think the heat generated by sustained charging at 5.5 A is often enough to lift the temperature into the higher current brackets without additional battery heating. I've observed my battery at ~16ºC in the morning after a night of charging in low outdoor temperatures. YMMV of course.