New Low Voltage Recs???

[bigbristv]

The last two rcs I bought (Losi Baja Rey 2.0 & Team Associated Reflex 14b) both came with LVC set at 3.0v tunable down to 2.6v

Both of these were for 2 cell lipos. Am I missing something here? I thought good practice was to stay well above 3v for overall battery & personal health.

 

[Hector_Fisher]

I've always considered that Lipos experience voltage sag under load. Voltage may drop down a few 0.1v's during use, but once the load is removed (the RC is idle), the voltage will relatively quickly return to a higher resting voltage.

That said, i've always assumed that manufacturers did this to get your lipos to end AT 3.0v, instead of cutting off at 3.0v. If you were running your truck really hard, i don't suspect it would too much of an issue to have it drop below 3.0v for a few seconds and then pop back up. The only problem is that is not something you could rely on. That assumes that all lipo cells are perfectly matched (which we know isn't always the case). And that also assumes you are always running it hard at the end of the pack (which also isn't the case).

I generally use the max (highest) LVC setting nowadays. There really isn't that much juice below 3.4 or 3.5v per cell anyway.

 

[dure16]

It’s wise to keep it over 3.2 V/C.

 

[Garcbomber]

Always start with max LVC and re-evaluate once it goes into limp mode, give the pack time to get back to room temp and check charger Total Voltage. High C discharge Lipos will amp draw better at the end of the discharge trigger, any cells under 3.3V is not good for longevity IMO. Especially if all cells are not congruent (within .05VDC).

Getting an extra minute of runtime at the expense of a $100 pack is not worth it.

 

[bigbristv]

All good points. And since the cost of replacing these nano-sized 2-cells is negligible to some, I'm more concerned with safety. I make sure to charge my larger bricks in safe bags, but these small ones?

 

[KnowAir]

I used to set the LVC down to 3.2v when available..but then realized that the few extra minutes of run time "just ain't worth it".. so, now it's 3.6v for lower draw rc's (stock power), 3.4v for the power hungry rigs, which I don't have but 2 of. My philosophy is that the rigs that pull more juice are also more likely to create voltage sag in the batts. Lower draw setups are less likely to sag. So the voltage measured by the esc is more accurate in a low drain setup.. I may be wrong, but I've been doing it this way for the last year or so.

 

[Dales396lt4]

I'm so over LVC! I used to run it down to LVC all the time. But I have found that like my airplanes I start to lose focus and that is when I make mistakes. So now I just run or fly until I feels it's time to take a break. (10 to12) minutes. When I check my Batteries most of the time, they are at 25 to 35%. This works for me.

 

[KnowAir]

I'm so over LVC! I used to run it down to LVC all the time. But I have found that like my airplanes I start to lose focus and that is when I make mistakes. So now I just run or fly until I feels it's time to take a break. (10 to12) minutes. When I check my Batteries most of the time, they are at 25 to 35%. This works for me.

Not a bad recipe either.. I know many like their 10ah packs, but honestly I'm good with 5-6ah for a stock rig, gives me decent run time, electronics are less likely to overheat as well.

 

[bigbristv]

I used to set the LVC down to 3.2v when available..but then realized that the few extra minutes of run time "just ain't worth it".. so, now it's 3.6v for lower draw rc's (stock power), 3.4v for the power hungry rigs, which I don't have but 2 of. My philosophy is that the rigs that pull more juice are also more likely to create voltage sag in the batts. Lower draw setups are less likely to sag. So the voltage measured by the esc is more accurate in a low drain setup.. I may be wrong, but I've been doing it this way for the last year or so.

Ok, see, now I think I'm getting it. Lower voltage draw would more likely not suck the available voltage down to points of no return like my 8/10awg systems.

 

[KnowAir]

Ok, see, now I think I'm getting it. Lower voltage draw would more likely not suck the available voltage down to points of no return like my 8/10awg systems.

No, any load can run the batteries down below the safe threshold. Though a heavy amp load can trick the ESC into LVC prematurely. A lighter load will be more consistently read by the ESC circuitry, so less likely to hit LVC prematurely.
I would recommend leaving it at 3.4v or higher until/when you feel comfortable setting it lower.
The best advice I can give is to check cell voltage after the battery has been run to LVC in the RC. Batteries will always "rebound" to a higher voltage after a few minutes of "rest" after being run down. 3.0v per cell is the lowest I've heard is safe, though 3.2v is a safer bet. This is after a few minutes of "rest".

 

[bigbristv]

Thanks. Incidentally I just took my Mojave out for a light spin after having fixed the steering issue and ran at least two of the cells on the 6s pack down below 3v

It's on a balancer now doing well so far. This is only the second time I've used this pack. LVC was set at 3.2 iirc.

 

[KnowAir]

Thanks. Incidentally I just took my Mojave out for a light spin after having fixed the steering issue and ran at least two of the cells on the 6s pack down below 3v

It's on a balancer now doing well so far. This is only the second time I've used this pack. LVC was set at 3.2 iirc.

Yeah, I'd bump it up, 3.6 if that's an option. At least until you know how things are playing out. There's always variables with each brand, both batteries and esc's. Better safe than sorry, like I (and others) said previously, better off stopping early than going too far and over discharging the battery. Enjoy brother!!