Do flooded batteries prefer 10 percent or higher discharge?

Of course the amount of furnace AH used depends on the RV. In the 5er barn it was a lot. 35F ambient. In the MH we have now, not so much.

30% charging rate from 50% SOC will not boil the batteries at all. In fact you get to Vabs at 60.X % SOC and then amps taper. The trick is to restore enough AH in a 50-80 or 50-90 to get by till next day's recharge.

You have to juggle AH use in a day vs how big a battery bank your RV can carry, vs how big a charger that needs, vs how big of a generator can you carry. We got away with it with the 5er because the Honda 3000 went in the truck. With the MH (see photo in Profile) no room for that big Honda (and no built- in gen), but also it is easier to heat.

You do what you have to do.

BFL13 wrote:
" When it comes to charging, I would not charge my FLA's at 30%"

BC is not in the PNW of course, but if you ever camp here in a provincial park in February, with your furnace eating over 100AH a day, plus whatever else you are doing 12v-wise, you would have to.

BC Campground rules say gen hours from 9-11 am or else wait till after dark 6-8pm. So if you want to get your 50-80 or 50-90 done in that two hours 9-11 when you can see what you are doing, you will need a high amp recharge and a big enough generator to run that high an amp charger.

Or else forget it, and stay home! :)

Wow!! 100A/H in a day!

I think you need a new furnace. In weather comparable to Vancouver BC I use 1/3 that.

There is definitely a limit to how fast you can charge FLA batteries without damaging them. 30% of C20 is going to boil your batteries and require close attention to electrolyte level. Ignore that and you will destroy your batteries.

" When it comes to charging, I would not charge my FLA's at 30%"

BC is not in the PNW of course, but if you ever camp here in a provincial park in February, with your furnace eating over 100AH a day, plus whatever else you are doing 12v-wise, you would have to.

BC Campground rules say gen hours from 9-11 am or else wait till after dark 6-8pm. So if you want to get your 50-80 or 50-90 done in that two hours 9-11 when you can see what you are doing, you will need a high amp recharge and a big enough generator to run that high an amp charger.

Or else forget it, and stay home! :)

The shareholders at Chevron really prefer you charge at 10% if using a generator.

Money rules. I am not spending an extra hundred dollars to save sixty dollars in battery life while charging them on a generator :)

I to would wonder why you would be discharging a battery for no reason ??
If you think that is somhow beneficial to a battery, you are grossly misinformed

I am curious as to why you are manually discharging your batteries?

Fast or slow discharge, within reason, will not have significant impact on battery life.

When it comes to charging, I would not charge my FLA's at 30%. If you do, keep a CLOSE eye on your electrolyte levels and top regularly with DISTILLED water.

8-13% of C20 is closer to ideal.

wopachop wrote:
For charging I see a spec of 10-13 percent of the 20ah rating.

I'm manually discharging in the garage and curious if flooded wet cells prefer a strong discharge? Or is something like 5 percent sufficient?

Charging at 10% is recommended for longest battery life, but the typical deep cycle (eg 6v golf car or a T-1275) can take 30%. The higher rates are necessary for short gen times doing 50-80s while camping.

Discharge rates similar for battery life. 25% discharge is about max for the internal chemistry to keep up.

A long slow discharge leaves the battery undercharged that whole time, so you would want to recharge it to full real soon and maybe even do an overcharge on it.

You do what the job requires and get new batteries as needed for that. Can't let the battery decide whether you can do the job!