Lipo batteries

[mick29]

Hows it going this is proberly a questions asked alot but im going to ask it anyway, what is the best way to look after your lipo batteries I have had two batteries the same but one packs up along time before the other even though there charged and stored the same thanks mick29

[matelot]

It has to be not over-discharging them i.e. monitor them as often as possible;
use a decent balance charger;
storage charge when not in use;
stop flying if batteries overly warm/hot;
don't charge if overly warm/hot;

Bound to be some more from others.

[tombo242]

G'Day Mick,

You're going to get a few answers on this one as many people think different ways. Here's mine (take it or leave it folks).

All of Keiths' suggestions plus:

1. Always bring your li-pos back to storage level after use. 3.8~3.9V/cell

2. Never leave them fully charged or discharged for any longer that it takes to get back from the field.

3. If stored for any length of time recharge to storage level every month.

I have batteries that are still good after 4 years flying so I know this works, I would never leave a fully charged battery overnight.

Li-Pos are dangerous items and have to be handled with care and attention.

Here's a link for a second opinion.

Tom.

[SkyHigh]

Fully Charged 4.2v per cell

Store Charge 3.7v to 3.85v

Fully Discharged 2.5v to 3.2v per cell

Store 3 cell = 11.55v

Store 6 cell 23.1v

[Burgess]

Hi Mick,

Get yourself a Watts meter and you'll be able to see what's happening to your LiPO during flight conditions. Have a look at the one via the link to 4-Max.co.uk in the Watts Meter thread.


Burgess

[laneritc]

Another lipo question, didn't get to fly from mid August to last saturday. got my MQX out batteries had been stored at 3.8 volts, charged a couple up with factory e-flight celeste charger on Friday night. before could fly two cycles of 6 minutes each, temps were in mid 40's after about five minutes low voltage waring kicked in, this happedon on both batteries. both recharged to 4.2 volts haven't got to fly again yet due to weather, is this normal for a battery after storage? never had this problem with 2 or 3 cell batteries. thanks for any imput, feels good to fly again, (batteries in question are 1s 3.7v 500mah 12c) Thanks Lane.

[tombo242]

Did you check for the 3.8V before starting to recharge? Once used, your batteries do tend to discharge while in storeage. It is best to check them every month or so and make sure that they are still at the right level.

If the storeage voltage is allowed to drop, you will get very much reduced flight times due to the increased internal resistance allowing the regulator to cut in. The battery will show a full charge, but if you check the mAh put back in after one of these flights you will find that it is proportional to the flight time. Checking the battery after it trips the regulator with a volt meter will show quite a high voltage, but if you check it under load, then you will see the reduced power.

Tom.

[laneritc]

Thanks Tom makes more sense to me now. So after several charge/discharge cycles do you think they will improve? Thanks Lane

[Andy456]

LVC settings are very dependent on LOAD. Many chargers will not attempt to charge lipos with voltages below 3.5 volts per cell. I have always used the below chart by IA-Flyer. Running your packs below 80% capacity is not good for them .... and I have packs with hundreds of discharges over many years that still perform as good as new.

Don't run past 80% capacity. Store at 50% discharge (3.80 - 3.85 volts per cell). These are the two rules I have always followed with excellent results.

4.20v = 100%
4.03v = 76%
3.86v = 52%
3.83v = 42%
3.79v = 30%
3.70v = 11%
3.6?v = 0%

Capacity below 3.7v "resting" is not usable for flying, it's where the battery voltage dump begins.

Every lipo discharge curve I have seen backs up the above voltage versus capacity data.


Regards.
Andy.

[solentlife]