Battery Drainage Responsibility

[SkyHighFlyGuy]

It was suggested to me by one of the tech guys at Yuneec that we should be landing H flights by 14.6. because of the lithiom battery type. We were once advised to run out batteries down to 1% (electronics in general) so you didn't undercut its next cycle potential... right? And apparently the phones and laptops nowadays can take a charge fine at any percentage. Anyway... the stock charger on H batteries usually gets me up to about 16.4 from takeoff. Apparently because once you hit 14.6, something about the quad nature of this battery (and because its not the same lithium drains it much faster, to levels that actually recovery potential of the battery. Longer flights, but shorter battery lifespan. EXPENSIVE BATTERIES!!! Any thoughts?

Also... model suggestions for overcharging? How much more flight time does it really get you?

And does anything provoke an emergency return-to-takeoff in default setup? Or if the battery does do I just expect to see it drop out of the sky one day...


Thanks!

SHFG

 

[BFD400]

Land at 14.7. There are a TON of post here regarding battery voltages. I would suggest that you search those out and read the advice from the people here that have been dealing with RC battery way more than me. They have it down to a science and can explain it in a matter that a child could understand.

 

[Brandon B]

It was suggested to me by one of the tech guys at Yuneec that we should be landing H flights by 14.6. because of the lithiom battery type. We were once advised to run out batteries down to 1% (electronics in general) so you didn't undercut its next cycle potential... right? And apparently the phones and laptops nowadays can take a charge fine at any percentage. Anyway... the stock charger on H batteries usually gets me up to about 16.4 from takeoff. Apparently because once you hit 14.6, something about the quad nature of this battery (and because its not the same lithium drains it much faster, to levels that actually recovery potential of the battery. Longer flights, but shorter battery lifespan. EXPENSIVE BATTERIES!!! Any thoughts?

Also... model suggestions for overcharging? How much more flight time does it really get you?

And does anything provoke an emergency return-to-takeoff in default setup? Or if the battery does do I just expect to see it drop out of the sky one day...


Thanks!

SHFG

Lipo Battery are extremely volatile ...do your homework and research on this...they can burn your house down if your not careful with them..no joke

 

[PatR]

I land by 14.8v, every time, periodically monitoring the battery indicator to assure I don't go below that level. I don't get as much flight time as those that wait until battery low indicators are triggered but I know I will not ever damage them, I will never enter a low battery auto land condition, and there is never a threat of losing the machine. My batteries come off the charger peaked at 16.74v as measured with a Fluke VOM, dropping slightly to 16.6v by the time they are flown. They do this every time. This is using the Yuneec kit charger. Long has it been known that if you want to keep your batteries for a long time and maintain the best reliability you don't discharge below 70% capacity and you don't charge them when hot, or charge so fast they become hot.

 

[Donp]

I agree with Landing at 14.7ish, my question to some of you with more experience...Do you take into consideration how far up/away you are? Like if you are 400ft up and 1000 ft away, do you start heading back way before 14.7 knowing it will take a bit of time to land?

 

[raptorheli2]

there is nothing special at all with this battery if you understand lipos.

be on the ground at 14.3v on the st16 and you will be fine, it is that easy folks.

the confusion comes from people who have no idea how lipos work and should really refrain from posting a number as it only causes confusion even if they have good intentions.

in the 20 years or so i've been flying models and since the day lipos came on the scene many years ago the rules have not changed with them.

 

[FlushVision]

there is nothing special at all with this battery if you understand lipos.

be on the ground at 14.3v on the st16 and you will be fine, it is that easy folks.

the confusion comes from people who have no idea how lipos work and should really refrain from posting a number as it only causes confusion even if they have good intentions.

in the 20 years or so i've been flying models and since the day lipos came on the scene many years ago the rules have not changed with them.

I'll second that.
The H batteries are fine down to 14.3v and even lower if push comes to the shove. I personally like to be in the process of landing at 14.4v and be on the ground by 14.3v.

I know that some people like to be cautious landing at 14.8 or 14.7 but there really isn't a need for it and IMHO they are just artificially cutting short their flight times...the difference between 14.8v and 14.3v can easily be in excess of 5 minutes...probably more!

 

[QuadBart]

I keep an eye on my Battery voltage. I start heading back if I'm far away at 14.8v. I typically land at 14.3 right when my warning goes off. Its been as low as 13.9 with no issues..

 

[BobW55]

Paladin came up with a pretty good guide some time ago.
Battery level guide
At 14.3 volts I am on final for landing.

 

[FlushVision]

I keep an eye on my Battery voltage. I start heading back if I'm far away at 14.8v. I typically land at 14.3 right when my warning goes off. Its been as low as 13.9 with no issues..

Because of a technical issue (posted elsewhere) on my very first flight it went below the second low level warning. I've no idea what the voltage was at that time because I was busy trying to land the bloody thing, but it must've been down towards 13.9v. I gotta say, though, that even at that level it performed well.

I must say, though, that it probably isn't a good idea to make a habit of that. Like I said earlier, I like to be on the ground at 14.3v...ideally just as the first warning comes through.

 

[raptorheli2]

I'll second that.
The H batteries are fine down to 14.3v and even lower if push comes to the shove. I personally like to be in the process of landing at 14.4v and be on the ground by 14.3v.

I know that some people like to be cautious landing at 14.8 or 14.7 but there really isn't a need for it and IMHO they are just artificially cutting short their flight times...the difference between 14.8v and 14.3v can easily be in excess of 5 minutes...probably more!

Quite correct.

I understand people think they are being safe but there will be zero, and I mean zero, discernable difference between landing at 15v and 14.3v to the life of the lipo.

Sure cycles take energy out of them and going too low is a killer for sure but people are wasting flying time by landing early and all they are doing is saving some charge time, no more, no less.

This type of device (drone) does not stress a decent lipo in any way, what kills them is massive amp spikes and running them too low generally speaking, poor cell quality also is a factor for sure. You simply can't spike a reasonable quality lipo enough to worry it in this hex.

Get a fast charger, set it to 6amps if you are concerned, be on ground at 14.3v and go enjoy the hex.

 

[Batfire]

Hi Guys,

Of all the post I have seen on this topic here I have to say PatR was most spot on. Figure to land around 14.8. that's 3.7v which keeps you in the safe zone. Emergency return back from a long flight I would say you are riding it close to failure if you go below 14v. Better to be safe and fly another day, than to push it and wonder why it just fell out of the sky. You should test your Y batteries and see the resistance reading then go get a good quality battery whether Gens Ace or venom and see their resistance readings. You might be surprised. Unfortunately we are stuck currently with Yuneec only batteries, hopefully soon Gens Ace and others will follow in with the excellent quality batteries. This is no add for those batteries just test them and see for yourself. These batteries are not of great quality.

Cheers

Batfire

 

[raptorheli2]

Sorry, that is inaccurate or misleading at best.

The landing voltage has already been covered many times and again, that voltage is way early but it is your batts.

The IR of these batteries is fine and very low for this use. All my yuneec batts are less than 2 which is great!

What they are like in 50 cycles will be the real test though but so far so good.

The irony is, gensace is the worst batts I have ever owned. I bought 6 pairs for a 3dhs slick and everyone of them puffed badly within 20 cycles. I may have got a bad batch for sure but the net result was the same as a cheap battery, tough luck and start again.

 

[Batfire]

Hmm.. ok, each has their own experiences here to relate and that's great that you have had your batteries last and test out like that. I was wondering what part of my comments are misleading and inaccurate or is it the whole statement?? I have done many test over the years and my statements of values are backed up by even the Lipo University site..... I can tell you from personal experience that If you get down to 10.5v on a 3S pack you are seconds from falling out of the sky. I will be happy to upload footage of that occurrence using a pac only charged at 1C twice with low resistance and no issues. That pack was a venom 5000mah 20C that I fly on my XXX-830. BTW after retesting pack and recharging it from that incident it has held up very well with no damage. I thought I would have to toss it due to the discharge to 10.4v it took when it fell from the sky lol (less than 2 feet fortunately). No damage to copter or battery. Less than 30 secs before failure i was 100ft up.

Cheers

Batfire
batfire's blog - RC Groups

 

[Rayray]

Holy Moly! These answers run the range regarding landing voltage. To each his own, if you're happy with the way you operate, keep it up.
I personally believe:
1) consistency with any rechargeable battery is good
2) the correct charge for LIPO's is 16.8 volts, which gives the max capacity. (LIHV's charge to 17.4, for the adventurous.)
3) when you land, it's typical to see the voltage jump up, like from 14.3 to 14.5 or more. 14.0 under load is going to be higher when you remove the LIPO and put it on a charger. No, I'm not saying you should fly to 14.0.
4) heat is the enemy, whether of electronics or batteries. Or people. Keep cool.

 

[KEN TARDIO]

QUESTION: Sometimes I don't use nearly all of the battery on the H. When this happens I discharge the battery and stop when the 1st cell hits 3.80. ( I have connectors) I have always done this with all my LiPo batteries over the years and never had a problem and have always had healthy batteries. If I am not going to use the battery for a long time I just leave them at 3.80 per cell as the storage charge. Does this seem appropriate?

 

[Batfire]

Sounds good to me Ken you can run down to 3.7vt but that is only 30-45 secs longer I would think. Always charge at 1C? I never push the batteries. I agree and here is a great article I am not sure where I found this or who sent it to me.............A Guide to Understanding LiPo Batteries
The part that really has meaning to me is the part about the IR checks. I have the Tenergy 5in1 and its fast and easy to do checks and record the data in spreadsheet on all my batteries. Most dont really understand the whys and how it affects copter performance. He does a nice job explaining why.

cheers

Batfire

 

[raptorheli2]

Batfire, the drone wont fall out the sky at 14.3v and as long as you never get to 3.3v per cell under load you have capacity left. I always land at 14.3 and the batt quickly recovers to 14.5v, perfect.

The part about the yuneec batts you said was inaccurate, there is nothing wrong with them from a spec and ir standpoint. I only have about 15 cycles each battery so early days but ir is steady with them thus far and in line with my other batts. The best ones i have are 0.8 IR but it will be same as the yuneec ones within 10 cycles in my experience after a few flights in the helis. As a comparison even my hobbyking turnigy batts are the same IR as these yuneec ones and those are decent for the money.

Buying expensive batteries is no guarantee of getting a good pack, all makers have good and bad cells. My lipo sponsor has sent me some shocking packs to test in the past and sent me some amazing ones too that are still going. I use them under high loads though so generally speaking i only get max 80 cycles and they are in the bin. You cant spike 150amps plus and keep them running no matter what the C rating is, that is a nonsense figure anyway but one for another time.

 

[Batfire]

I will leave you to your own experiences, but when you ride the batteries to the edge, sometimes you fall off. Plenty of videos on youtube, vimeo, etc.. demonstrating what happens when you ignore the buzzers, beepers,vibration alarms and they all did it their way. If nothing else riding a battery down to its minimum voltage takes away from its life span. As far as my experience with battery failure at 10.4v on a 3s pack that is valid and I have footage to prove it. That was an accident I learned from and will never allow to occur again. To do it on purpose is downright foolhardy and expensive.

As they say each to their own. Do what you believes works for you. I would not tell new people to this hobby its ok to do what your saying because that is teaching bad habits and they will get bite at some point pushing the battery to that level. This is where as I stated earlier IR checks are so important.

Cheers

Batfire

 

[Rayray]

If I am not going to use the battery for a long time I just leave them at 3.80 per cell as the storage charge. Does this seem appropriate?

Sounds good. Manufacturers have the storage voltage on the LIPO label. 14.8 typically, 3.7 per cell times 4. Roughly 50% capacity.