Lipo Voltage - Full / Storage

[Ge0rge]

So I received two SMC 2S 60C 7.4v 9400mah Lipos for a new Summit, and the paperwork says the cells are at 382 and 383. Hooking them up to a Duratrax Onyx 245 charger the total for each battery is at 7.64v.

Looking at the SMC paperwork, a 2 cell pack should = 7.4v to 7.8v.

This means that the packs are fully charged, correct?

Do i need to do something with these until xmas while they are in storage so I do not cause damage or reduce cycle life?

Thanks for the help!!

 

[Szczerba]

A fully charged 2s pack will be 8.4v. If you will not use them for a few weeks, voltage around ~7.2v is fine for storage. Storage voltage is best 50-70 of voltage.

 

[Ge0rge]

Great, thanks. Is it worth while to buy a voltage analyzer? I heard good things about this one in particular: HobbyKing HK-010 Wattmeter & Voltage Analyzer (AR Warehouse)

I know the charger I have will do this but this seems a bit less time consuming for a quick check.

 

[Szczerba]

if you are looking for a quick voltage checker, pick up something like this. I carry this around with me while I am running my trucks to check batteries before and after use. Plugs into battery balance plug. And side note, I balance charge my lipos 100% of the time.

Dynamite LiPo Cell Voltage Checker [DYN4071] | Radio Control - AMain.com

 

[JohnRobHolmes]

3.6 to 3.8v per cell is a good storage point

 

[Selser420]

Having a voltage checker is great for when you are on the trail. I also find I use mine a lot in the workshop to check batteries.....sometimes I forget to put a rubber and on them after I charge them (my system for knowing what's charged and what's not

 

[Ge0rge]

What is the lowest voltage you want to take the battery down to?

 

[k7zpj]

Minimum rated is usually 3.0v per cell. I have my lipo cut off set at 3.4v per cell to give a bit of a safety margin.

 

[Olle P]

Minimum rated is usually 3.0v per cell...

Now that's with the cell in rest.
Cells won't be in danger until the resting voltage drops below 2.8V.
The voltage is lower while current is drawn, so the low voltage cutoff (LVC) must kick in before any cell drops to ~2.6V during use.

With LVC set to 3.4V/cell (with current) it will break at ~3.5V resting voltage when there's ~40% charge remaining. That's only good if you're flying a helicopter or so and need to fly it back home to land after the alarm kicks in and still not drain the battery.

I set my LVC to 2.8V/cell which makes it activate at ~3.2V resting voltage.

 

[JohnRobHolmes]

I put mine at 3.4v as well, and charge to 4,15v. Instead of 30 cycles I get closer to 100 before capacity falls off.

 

[Selser420]

I set my LVC to 3.0 and usually end up with a resting voltage of 3.4-3.5v

 

[Ge0rge]

I read how to turn the lipo low voltage detection on, but I do not see how to set the limit? Is it preset only, if so, at what voltage will it kick in?

 

[rcaholic13]

Mine normally kicks when battery is at about 3.60 to 3.80