The E-sky 2&3 cell balancer charger (EK2-0851) manual states:
"Compatible battery: 11.1 V, 1000 mAh, 7.4 V, 800 mAh"
Does that give the max limits of C rating and mAh rating?
Particularly, can I charge a Turnigy 1600mAh 3S 20C Lipo Pack with it? :help:
I think you can.
A charger that can charge a small capacity lipo can also charge a large capacity as long as the charge rate is not greater than the safe limit. Im guessing the esky charger is a slow charger so should be ok. Only difference is that it will take more time.
The charger detects the charge completion by measuring cell voltage so it should stop charging by itself when complete.
Please wait for other opinions as well - im a learner too :)
Rajat
You've got your "fundas" right!
Yes you can.... You can even charge a 3 cell 5000mah battery with it. However it will take very long. Since the charger provides 1000mah in 1 hour, to charge a 5000mah battery it will take 5 hours from a flat pack.
Saurabh
It may take even longer as the charger just states "compatible battery 1000 mAH". No indication of its actual charge rate.
The manual also states "Practical charge current:750 mA" (and it has a 1A SMPS adaptor).
Does that mean the 1600 mAh batt. will take somewhere between 2-3 hours to charge?
That much time's not a big constraint right now, because the other option would be to buy another (costly) charger and wait for other stuff.
Will the E-sky suffice for now?
It will take that long only if the battery pack is dead.. ie 0MaH..
Most LVC's will cutoff with atleast a little juice left in the battery :)
You can safely charge it but as everyone said, it will take much longer than normal. Also you cannot really say that it will finish charging in 2-3 hours because it charges a lesser capacity battery in 1 hour since it also depends on reverse discharge rates and the type of battery being charged. I can't really remember the exact explanation since I had learnt it long long ago.
Since you're charging a battery that's just double the existing capacity, you shouldn't face too much trouble. Another thing to keep in mind is to check whether the particular charger has a current limitation. Ensure that you're not charging it unsupervised. Keep an eye on the temps as well. If after say 5-6 hours its still charging then you're better off getting a different charger with higher current rating.
If its shows as charge completed, test to see if your run-times are adequate for the battery's rating. If you feel that the run times are considerably shorter, then you need to get a different charger.
Quote from: Tassem on May 19, 2011, 04:45:59 PM
....If you feel that the run times are considerably shorter, then you need to get a different charger.
Why would the run times be 'considerably' shorter? Doesn't the stored charge depend completely on the amount of time the LiPo takes to get fully charged?
Some chargers recognize a battery as being fully charged by measuring the reverse discharge. So at times while a higher capacity battery may not be fully charged, the charger will still show it as fully charged. If it has a trickle charge option and if you leave it connected long enough, it may charge it fully.
So if this is the case with your charger, the battery may not be fully charged, hence giving you shorter run times.
The first thing to do is hook it up and attempt a charge. If there is no noticeable difference in run time and the charging duration is acceptable, you've saved yourself some money ;)
Quote from: Tassem on May 19, 2011, 05:58:53 PM
Some chargers recognize a battery as being fully charged by measuring the reverse discharge. So at times while a higher capacity battery may not be fully charged, the charger will still show it as fully charged. If it has a trickle charge option and if you leave it connected long enough, it may charge it fully.
Tassem,this is true for Nixx packs.For lipos,a completely different algorithm is used.Saurabh will be the best person to talk about that.
I had a feeling things will be different for LiPos. But I'm guessing LiPo's use reverse discharge from individual cells due to the balance charging facility?
Quote from: Tassem on May 19, 2011, 06:08:20 PM
I had a feeling things will be different for LiPos. But I'm guessing LiPo's use reverse discharge from individual cells due to the balance charging facility?
Lipos just keep charging(even beyond 4.20V/cell) till they blow up :D .The charger stops at 4.2V/cell.You can have it stop at 4.19,4.18v/cell as well.The final stage is for balancing.It starts of with how much ever current is specified.Later on,the current decreases.On advanced chargers,you can adjust when it reaches this stage.I'm no expert on charger behaviour but this is roughly similar to what most chargers do.
Hmmm.. How can they indefinitely charge? Beyond a particular point the batteries will usually just start wasting energy as heat. I need to read up more on this..
They go up in smoke or flames if overcharged for a long time.Lipos do crazy things when abused.