Outcast Low Voltage cutoff? gensacearespammers 4s 100c 8000mah

[Martyrc]

Hello,

Im fairly new to arrma so please don't bite my head off. I recently bought the outcast 8S EXB rtr with the gensacearespammers 4s 100c 8000mah batteries. Its seems to shut down while I have 40% battery left everytime, which seems a bit high to me? Power shuts off and ESC starts beeping. From reading the manual I'm guessing its the low voltage cutoff kicking in? Its at level 5 by default, is it safe to go lower with the batteries I'm running?

 

[Eno]

What is the voltage of your cells when LVC gets activated?

Under load the lipo shouldn't fall below 3.3V per cell.

 

[Diem Turner]

Hello,

Im fairly new to arrma so please don't bite my head off. I recently bought the outcast 8S EXB rtr with the gensacearespammers 4s 100c 8000mah batteries. Its seems to shut down while I have 40% battery left everytime, which seems a bit high to me? Power shuts off and ESC starts beeping. From reading the manual I'm guessing its the low voltage cutoff kicking in? Its at level 5 by default, is it safe to go lower with the batteries I'm running?

That's definitely your LVC cutting in. Go ahead and set the LVC lower. The one thing I'd say you really want to avoid is draining the batteries below 3V/cell. From what I've read that's where you start running the risk of damaging cells. Your battery isn't going to explode if you do go below 3V, when talking about damaging the cells these are small scale damages inside the battery that can, over time cause so-called spikes to grow from anode to cathode (or the other way around) and if/when that spike contacts the other side, that creates a dead short inside the battery...and that is what is actually bad. But that won't happen from one or two blips below 3V. But Lipo fires are no joke and, if stored in the wrong place near flammable material, whole houses can get taken out by one battery. If you've never seen a lipo fire, I recommend getting on Youtube and looking at some videos so that you get a better understanding of what you're dealing with there.


Disclaimer: No heads were bitten off in the making of this post. Any similarities to batteries crispy fried or alive is purely coincidental.

 

[Martyrc]

What is the voltage of your cells when LVC gets activated?

Under load the lipo shouldn't fall below 3.3V per cell.

They are storage charged now, but I think I remember seeing 3.7 or 3.8.

That's definitely your LVC cutting in. Go ahead and set the LVC lower. The one thing I'd say you really want to avoid is draining the batteries below 3V/cell. From what I've read that's where you start running the risk of damaging cells. Your battery isn't going to explode if you do go below 3V, when talking about damaging the cells these are small scale damages inside the battery that can, over time cause so-called spikes to grow from anode to cathode (or the other way around) and if/when that spike contacts the other side, that creates a dead short inside the battery...and that is what is actually bad. But that won't happen from one or two blips below 3V. But Lipo fires are no joke and, if stored in the wrong place near flammable material, whole houses can get taken out by one battery. If you've never seen a lipo fire, I recommend getting on Youtube and looking at some videos so that you get a better understanding of what you're dealing with there.


Disclaimer: No heads were bitten off in the making of this post. Any similarities to batteries crispy fried or alive is purely coincidental.

Alright, good to know and thank you for all the info!
They are stored in a lipo safe bag which is near a door so I can potentially kick the bag out in a heartbeat. I storage charge them after every run. Seen some youtube vids and they are scary for sure.
Nice disclaimer haha

 

[Eno]

3V/cell

That is way too low IMO.

 

[Diem Turner]

That is way too low IMO.

Way too low for what? Below 3V is where you begin to run the risk of damaging cells. If he's in the situation where the batteries are at 3.4-3.5V/cell and they're just dipping below 3.3V under load, setting the LVC a bit lower so that he can run them down to storage voltage will do no harm. Additionally I was giving him an absolute bottom that is to be avoided and I warned him about possible consequences. Again, what I suggested he do will allow him to drive his batteries until they actually hit storage voltage. This will save him the need to hook his batteries up to a discharger every time he goes home. I'm just looking at it from a pragmatic perspective and I didn't suggest that he do anything risky. I didn't tell him to drain them below 3V/cell, that's what I told him to avoid.

They are storage charged now, but I think I remember seeing 3.7 or 3.8.


Alright, good to know and thank you for all the info!
They are stored in a lipo safe bag which is near a door so I can potentially kick the bag out in a heartbeat. I storage charge them after every run. Seen some youtube vids and they are scary for sure.
Nice disclaimer haha

Solid. Storage voltage is anything between 3.7 and 3.85V/cell so it sounds like you're right where you need to be. FWIW, don't put too much trust in lipo safe bags. They'll gain you a second, maybe two over them just lying open. Those bags don't really do much against a runaway lipo meltdown. Just sayin'.

 

[Martyrc]

Way too low for what? Below 3V is where you begin to run the risk of damaging cells. If he's in the situation where the batteries are at 3.4-3.5V/cell and they're just dipping below 3.3V under load, setting the LVC a bit lower so that he can run them down to storage voltage will do no harm. Additionally I was giving him an absolute bottom that is to be avoided and I warned him about possible consequences. Again, what I suggested he do will allow him to drive his batteries until they actually hit storage voltage. This will save him the need to hook his batteries up to a discharger every time he goes home. I'm just looking at it from a pragmatic perspective and I didn't suggest that he do anything risky. I didn't tell him to drain them below 3V/cell, that's what I told him to avoid.


Solid. Storage voltage is anything between 3.7 and 3.85V/cell so it sounds like you're right where you need to be. FWIW, don't put too much trust in lipo safe bags. They'll gain you a second, maybe two over them just lying open. Those bags don't really do much against a runaway lipo meltdown. Just sayin'.

And now I cant sleep at night Should I buy one of those ammo cases?

 

[Diem Turner]

And now I cant sleep at night Should I buy one of those ammo cases?

Yes.

Edit: If you do, don't forget to take the rubber seal out of the lid so it can vent. If you don't, you'd essentially create a pressure bomb (I'm not saying it would definitely explode cuz those things are pretty tough but, you really wouldn't want to open that thing).

Edit 2: There's no reason to let it bother you. Unless your batteries are damaged, puffed up or have some other clear indication that they've been abused, lipos are very stable at storage voltage.

 

[LazloZ28]

I had this same thing happening on my 3S. It's a momentary drop in voltage when you gun it, the battery dips below LVC for just a split second then recovers. On that ESC there was no setting, so I just counted that as dead battery, or baby it once you reset it. If you can adjust the LVC in the ESC you can get a separate lipo alarm that plugs into the balance leads and lower the LVC.

I bought a small and large Bat safe(small for charging and large for storage). They're not exactly cheap, but it's really just for peace of mind. At the time, I was in an apartment so I had to store everything inside. Ammo can is fine for fire in a garage or shed, but does nothing for the smoke. That said, none of me or my friends have experienced a lipo fire, they do happen, but not really worthy of being scared of if you manage your batteries properly.