Maximum discharge for LiFePO4

[SageRpod]

Hi all. I just finished my first mod on our new 5.0. I installed 2 additional HUBLiON batteries which I purchased from ETI when we picked up our Escape for a total of 400ah. It was an easy install with plenty of room to work.

I noticed that ETI set the maximum discharge limit to 30% but I have read that LiFePO4 batteries can go to 20% and even 0 occasionally. What are all of you setting your lower limit at?

[nepaweb]

The recommended discharge floor for my Battle Born batteries is 0%. I have mine set at 10%.
Looks like the Hublion batteries have similar specifications to the Battle Born.

Would love to see a picture of your battery install when you get a chance.

[rubicon327]

When you say “setting maximum discharge limit” is this on the Victron BMV? I have an aftermarket install with 400AH lithium and have a low SOC alarm set for 20% on the Victron. If I’m that low I really want to be alerted with some time to spare and plan corrective action. It doesn’t stop any discharging it’s just an alert. In theory you can go lower but we try to not beat up the battery too much. If you are referring to something entirely different I apologize.

[Perry Butler]

It depends on the BMS. I believe BattleBorns are actually 105-110 ah batteries but to survive in the hands of consumers their BMS only allows 100 ah’s to be used. Don’t quote me on these exact numbers though. So in reality if you’ve used 100 ah’s from the batteries you actually have 5-10% left, but you’re in a danger zone where BattleBorn and other companies are not comfortable, so they choose to use a 5-10% overhead.

Tomorrow we install our two 100 ah SOK batteries with Bluetooth and a Victron BMV-712 battery monitor. I don’t know what SOK’s overhead is and don’t care. I do know I will not be taking them to 0% state of charge. Using past practice, we’ll use 30 ah’s a day and hope we can fill 15 ah’s every day. At that rate we’re good for 12-13 days before we need a full hookup site. We also have our 100 watt portable to use if needed. It will be interesting to see if the SOK’s charge as fast as our SiO2’s. Even with 170 watts our SiO2’s had no problems staying 90% SOC in our 2021 winter with only 170 watts.

Enjoy,

Perry

[John in Santa Cruz]

The YouTubers who tested the SOK batts ran them til the BMS shut them down, and got the rated 206 AH or better, they did this several times, so I'd say 100% to 0% is just fine. I've never had mine below about 45%, and that was 9-10 days of dry camping with no sun.

[SageRpod]

Thanks for the info. I will probably set the alarm at 20% but set the floor at 0 for my application. I doubt we will even come close to 20% with the 4 HUBLiONs. Heck we've been camping successfully for years with two 100ah lead acid batteries in parallel and 130watt solar suitcase kit.