Lipo habits and care

[helimadness]

Hi All.
So my typical process is Parallel charge my 5 lipos (6s 2600 mah) up the night before and head out flying the next day. timer is set to 5:30 and they all come back really close around the 3.75-3.78 mark. Get home and put them into a storage charge for the week so they all stay balanced at 3.8v.

I measured the last couple of chargers and put back about 1800 mah per pack.

So my questions are.

1) Am I using 70% of the pack?
2) Can I use more?
3) Should I cycle them on the charger through there full range every now and then?
4) After about 25 Cycles the IR is around 1.5 which I think is good? (My charger doesn't display IR but every now and then I charge on a cellpro at the field so can check)

They seem to be doing well just don't want to get into any bad habits and shorten there life.

Cheers

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Trex 500 EFL Pro
JR XG 7
Mini CP

[PeteStewardson]

I use a spreadsheet to log all my flights. You do need to charge the packs to work out the mah put back in correctly though.

My spreadsheet does all the work for you, just put in flying time and the mah put back in and it will give you the % used, and your max flight time based on that average usage over that flight using 80% of the lipo.

Flight logging | RCHeliBlog.co.uk

[muscleflex]

^^ Pete, do you charge your packs when you get home then? what if you are not going to fly again until the next weekend? do you leave them in their discharged state and just charge the night before or something?

[rhysduk]

Pete, you Spreadsheet doesn't calculate the %...

Ah wait... I'm using Office 2003 (work) so it may not have converted it properly.. ignore me

[PeteStewardson]

^^ Pete, do you charge your packs when you get home then? what if you are not going to fly again until the next weekend? do you leave them in their discharged state and just charge the night before or something?

Yes I charge when I get home. Unless I'm not flying for a week or I leave them charged, if I'm not going to get out for a while ( with the 700e as an example ) then I charge, then discharge to storage. At least then I have a record of what I've used on a flight. My 500 packs, and 450 packs I just have charged all the time. I fly most days anyway ( flew 4 packs on the 500 this lunch )

Pete, you Spreadsheet doesn't calculate the %...

Ah wait... I'm using Office 2003 (work) so it may not have converted it properly.. ignore me

I've just checked, there's a problem with the spreadsheet I've uploaded. The first two lines don't work and you'll need to copy the formulas from lower down to make them work on those two lines

[cjcj1949]

You can use more if you want but what you are doing is about right. It depends on how warm it is as well. You can get about a minute more in the Summer than the Winter due to IR dropping as temperature goes up. I go by the voltage under load. Between 3.6V and 3.7V is about right. The better the lipo the higher you set the on load voltage. Noone really knows what you can get away with, but there doesn't seem to be a free lunch. If you have longer flights your batteries won't last so long.