gottabaja

iTrader: (3)

Well after a few calls, I found that at least one company say's that a lipo
batteryies ideal operating temp is 100 degrees fahrenheit. Which really threw me for a loop. Since I was under the idea that they should be at room temp not much higher then 80-85 degree's.

Any thought's on this ideal, or experience in this area.

Duster_360

iTrader: (21)

This is what these were for -

http://www.horizonhobby.com/Products...235#reviewsTab


I believe the reason they're discontinued is they're illegal for sanctioned racing. If you're a top flight racer, maybe you could see some effect from pre warming lipos to optimum temps, but I'm betting its slight. If this was a big deal, it would be discussed a lot, and its not.

About the only lipo related temperature discussions you see involve what temperature to store them at long term or running/charging them when its cold where you're running.

gottabaja

iTrader: (3)

I am looking at like a noob would. As you see the discussion's on lipo temp's it leads them to think any rise in temp is a bad thing, which is not true at all.

In my case I was looking to lower temps in a 1/5 scale conversion and the battery manufacture said it would be better if I ran them at around 110 degrees. It would actually help my run times.

Duster_360

iTrader: (21)

Surface RC is typically way over batteried, always been that way, prob always will be. Elec planes otoh ar eunder batteried - if they have a good setup, those lipos run 110-115F.

Some guys were using heating pads as warmers until all that stopped. Its going to be hard to get to a set temp.

gottabaja

iTrader: (3)

Heating pad's you say...... I never thought of that. Thanks for that little tip.
Unless there is a reason that it stopped i.e FIRE

Duster_360

iTrader: (21)

Not really, the practice was used in racing for that extra littel edge and when it was ruled illegal, it stopped. I use ona heating pad for a bad back and it can overheat a lipo, so be careful. Find one with several temp settings/levels and experiment to find what level gets you closest to what you want temp wise.

Mine has 4 settings and will burn bare skin on the highest setting, so be careful!

Lazer Guy

iTrader: (1)

After e-mailing many company's about lipo operating temp's I was told to keep them at the same temp all day when in use.
Don't use them if they are below *60.
I temped my lipo's many times after my races in winter and they were *85 to *100, thats what temps I was told is good if you want them to last longer.

I tried many different things to heat them with and found a reptile/amphibian heater keeps them at no more than *90.
Just put one in your lipo bag well your charging and until your ready to race, after your race put them back in the bag well there still warm.

vlad_vy

From ROAR letter

...
It has been known for many years that Lipo packs have an optimum discharging temperature of about 110degF. This means that a pack at 110degF will maintain higher voltage under load (due to lower internal resistance) than the same pack started at 70degF. The pack started at 110degF also tends to gain less heat during the discharge and finish the discharge cooler than the pack started at 70degF when discharged near its full capability (again a function of lower internal resistance). Warming lipo packs to or near their optimal discharge temperature has also shown positive benefits to their cycle lifespan (how many times they may be charged and discharged before showing degradation in performance, which signals the end of their useful life).
...