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Old May 23, 2013, 12:35 AM
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Originally Posted by dacaur View Post
I got out of nitro years ago. These days it has absolutely no performance advantage over electric, and the cost is negligible over time, going more toward electric advantage these days.... I have spent enough time fiddling with nitro engines to last a lifetime or two. Pass.




Yea, I can do math. My whole point is that my time is more valuable than getting maximum life out of a battery... I thought I made it pretty clear that I would rather spend $20 on $10 worth of battery if it meant more flying time and less stress. I can replace a battery that goes south prematurely, but I cant get back time spent charging when I could be flying.

If I charge after I fly, I am not charging when I could be flying. Like I said (and you quoted) I don't take a charger to the field with me, so "after I fly" means after I finish flying, pack up, and get home. If I have to charge it up before I fly, that's time I could be flying. No offence but did you even read my post or just skim it? I mean, you quoted it, but then your next paragraph makes me believe you didn't read it.... Here it is again "when I fly, there is often not a lot of "pre planning" I will notice the wind is low, and go fly. I don't take a charger to the field with me, so there is no "charging on the way" I don't want to go "oh awesome, no wind, I better run home and spend an hour charging my batteries!"..... Many times I have only been able to get 1/2 hour of flying in even with the batteries [pre] charged, so if I had had to charge them, I would have gotten NO flying in (due to the wind picking up or darkness setting in)"

Even assuming I have some fancy parallel charging board, charging from a "storage" charge is going to take me 1/2 an hour. Thats half an hour that I don't get to fly. 1/2 hour delay before I leave for the park. When there is only 1/2 an hour of flyable light or wind when I get to the park, that 1/2 hour spent charging means a lot to me. That half hour is worth doubling the price of a $10 battery... Of course, the example of getting 50 flights instead of 100 is a worst case scenario, I get more than 50 flights from my packs.... Plus, since it takes me months to get those 50 flights, before I have to buy a new $10 battery, I think I can handle it....
I spend more time flying gas than glow. Less stress, I've seen more guys need stitches from electric planes. Haven't seen too many guys fly electric for 15min and only use 50% of their battery. And I never suggested that you should try them.

Did you read my post, I never said liquid fuel had a performance advantage I said I flew it because it is ready to go when I am, for the same reason you charge your batteries after you are done flying. And yes I do still have some electric planes.

Yes I read your post. I understood what you said first about having more flying time by charging your batteries after flying so they are ready to go for the next time. Then in another paragraph you were talking about the cost of batteries and how you were saving time charging them without reference to flying time. I didn't think you were just repeating what you had already said, that seemed redundant and it was in a different context.
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Old May 23, 2013, 01:30 PM
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FWIW.. I can have 12 batteries 2200mAh (six x 3s and six x 4s) charged from voltage as taken off the plane to fully charged in about 15 minutes. This is about the same time as it takes me to make my excuses to the wife, and put my planes in the car.

What's more if I fly in the morning and I can charge them all again for an afternoon session, and once again in the evening if I want... Try doing that by pre-charging days in advance!

Yeah, i did stump up for an expensive charger

PS.. yes in theory i could do this with gas/glow too but due to noise that would mean a 45 minute drive across town to a club field. That's 1 1/2 hours that I could be flying at the sport field at the end of my road. As i only typically get out for a couple of hours to go flying by the time set up and 'putting away' time is factored in it would basically mean no flying for me

Each to his own though, if you are lucky enough to have good access to a gas/glow flying field and/or can get away for a whole day then it's not an issue.
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Old May 23, 2013, 02:47 PM
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Originally Posted by 600Bob View Post
Do not ever discharge it to 3v per cell. It is best to never discharge below 80% of capacity in MA., that would be 2400ma used from your battery. Best to leave them near storage voltage of 3.85v per cell. Don't leave them sitting fully charged for days or weeks.
3.0v per cell is a bad idea? That's troubling - I just got my Triton 2 charger, and in the discharge mode it only supports cutoff voltage of 3.0v per cell ... so for my 3S 2100mah packs, I can only select 9.0v or 12.0v cutoff voltage.
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Old May 23, 2013, 03:11 PM
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Originally Posted by netarc View Post
3.0v per cell is a bad idea? That's troubling - I just got my Triton 2 charger, and in the discharge mode it only supports cutoff voltage of 3.0v per cell ... so for my 3S 2100mah packs, I can only select 9.0v or 12.0v cutoff voltage.
I looked at the manual for your charger and I don't see a menu setting for storage charge, that is strange. I have never used a discharge setting for Lipos, if I have needed to discharge a full battery I set it to storage charge and it takes it down to 3.8v per cell. 3v per cell is considered fully discharged, even the low voltage cuttoffs in ESC are above that limit and it's hard on the battery to fly them that low.
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Old May 23, 2013, 03:46 PM
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Originally Posted by netarc View Post
3.0v per cell is a bad idea? That's troubling - I just got my Triton 2 charger, and in the discharge mode it only supports cutoff voltage of 3.0v per cell ... so for my 3S 2100mah packs, I can only select 9.0v or 12.0v cutoff voltage.
That would be used only if you wanted to discharge and dispose of the battery. No reason at all to deliberately discharge to that level otherwise.

I think that's a pretty old charger with no balance function and no 'storage' function either.
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Old May 23, 2013, 04:15 PM
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Originally Posted by JetPlaneFlyer View Post
That would be used only if you wanted to discharge and dispose of the battery. No reason at all to deliberately discharge to that level otherwise.

I think that's a pretty old charger with no balance function and no 'storage' function either.
That is really annoying, I'm amazed that the "discharge" feature on TritonEQ (a new charger, I believe it was just released last year and is highly recommended on other RCgroups threads?!?) is only useful for readying a battery for disposal
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Old May 24, 2013, 10:03 AM
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Originally Posted by netarc View Post
That is really annoying, I'm amazed that the "discharge" feature on TritonEQ (a new charger, I believe it was just released last year and is highly recommended on other RCgroups threads?!?) is only useful for readying a battery for disposal
I was looking at the wrong charger. I Googled 'Triton 2 charger' and came up with a old discontinued model.

The EQ is newer but still a four year old model, and four years is quite a long time given the way LiPo technology has moved on. The EQ does do balancing which is a big plus over the older model, but it still has that rather stupid 3V per cell fixed discharge end voltage .

You could of course just halt the discharge when it reaches optimum storage voltage.
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Old May 24, 2013, 06:35 PM
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If you set it to nimh or nicad discharge, you can choose the voltage to .1v....just dont try to cycle on nimh
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Old May 24, 2013, 07:11 PM
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Originally Posted by dacaur View Post
And then there is someone like me who has never ever even once used a "storage" charge and my packs are fine... I fly em, charge em up to 100%, and put them away till next time I fly em.... (weekend flier)

Am I reducing the life of my packs? Probably, but so what? If I only get 75 flights instead of 100 out of a $10-$20 battery, I can handle that.

Life is just too short to worry about things like that.... I have packs that were charged full then sat for 6 months. No swelling, and they still work fine.

If you are paying $50-$100 for a pack, I would recomend you DONT do what I do, but if you are like me and buy cheap batteries, dont lose sleep over keeping
the battery 100% charged for a week or two....
Could not have said it better, I'm with you on this one.
Bob
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Old May 25, 2013, 03:11 AM
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Originally Posted by dacaur View Post
If you set it to nimh or nicad discharge, you can choose the voltage to .1v....just dont try to cycle on nimh
this scenario, do you hook up the balance board, or just the +/- leads?
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Old May 25, 2013, 09:53 AM
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Originally Posted by netarc View Post
this scenario, do you hook up the balance board, or just the +/- leads?
It would just be the main power connector and you would have to set the target voltage for the whole pack, not the individual cell voltage (that would be a bad mistake to make)
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Old May 25, 2013, 11:03 AM
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Originally Posted by dacaur View Post
I got out of nitro years ago. These days it has absolutely no performance advantage over electric, and the cost is negligible over time, going more toward electric advantage these days.... I have spent enough time fiddling with nitro engines to last a lifetime or two. Pass.




Yea, I can do math. My whole point is that my time is more valuable than getting maximum life out of a battery... I thought I made it pretty clear that I would rather spend $20 on $10 worth of battery if it meant more flying time and less stress. I can replace a battery that goes south prematurely, but I cant get back time spent charging when I could be flying.

If I charge after I fly, I am not charging when I could be flying. Like I said (and you quoted) I don't take a charger to the field with me, so "after I fly" means after I finish flying, pack up, and get home. If I have to charge it up before I fly, that's time I could be flying. No offence but did you even read my post or just skim it? I mean, you quoted it, but then your next paragraph makes me believe you didn't read it.... Here it is again "when I fly, there is often not a lot of "pre planning" I will notice the wind is low, and go fly. I don't take a charger to the field with me, so there is no "charging on the way" I don't want to go "oh awesome, no wind, I better run home and spend an hour charging my batteries!"..... Many times I have only been able to get 1/2 hour of flying in even with the batteries [pre] charged, so if I had had to charge them, I would have gotten NO flying in (due to the wind picking up or darkness setting in)"

Even assuming I have some fancy parallel charging board, charging from a "storage" charge is going to take me 1/2 an hour. Thats half an hour that I don't get to fly. 1/2 hour delay before I leave for the park. When there is only 1/2 an hour of flyable light or wind when I get to the park, that 1/2 hour spent charging means a lot to me. That half hour is worth doubling the price of a $10 battery... Of course, the example of getting 50 flights instead of 100 is a worst case scenario, I get more than 50 flights from my packs.... Plus, since it takes me months to get those 50 flights, before I have to buy a new $10 battery, I think I can handle it....
Amen. I just have not had battery problems yet at least, but only been in this a couple of years. I have followed the example set by the locals that I started with to always keep my batteries charged and ready - you just never know when that perfect hour will present itself to go fly.
Just another thought, question or comment whichever you want to call it. I will not argue on this point, as I plain and simple do not know the answer, but have often wondered what the difference is in the end between the fly, charge em up and have em ready vs the discharge to storage, wait till the need arises, superfast parallel charge em up at high charge rate, to go fly guys. On one side, you store fully charged batteries, on the other, you put cycles on a battery that would not be necessary if you left them charged, charge at high amp rates which can stress things, and parallel charge with the chance of problems from that system. One typical method of expressing how good a manufacturers batteries are is theoretical number of charge/discharge cycles. If half the time I end up with a fully charged battery or two and discharge them when I get home, that is an extra cycle every time I fly.
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Old May 25, 2013, 11:44 AM
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I don't think there is a simple answer. I had three 'new' batteries given that had been kept fully charged for about a year. The guy actually topped them up every month as he thought it the right thing to do. All three had been rendered useless for my purposes, the voltage sagged so much that they tripped the LVC within a minute of take off. maybe some people with low amp applications would have thought them to be 'fine', but for me they were useless. When I first started flying electric I also killed a few batteries of my own within 20 or 30 cycles and I put that down to storing charged (no way to prove it of course).

I think that higher 'c' rating batteries may be slightly more sensitive to storing fully charged, but that's a theory based on a small sample so may be incorrect. One thing for sure, all the top battery manufacturers tell you not to store fully charged, they should know.

On the other hand we have people who report no problems?

Since working to simple to follow (and overall time saving) rules on battery care I havent had a battery die in the last two years. Several have got at least a couple of hundred cycles and they are still performing ok, if not quite 'as-new'.

As for 'extra cycles'.. nope, that doesn't hold water. you don't usually put extra cycles in a battery, all you do is charge it at a different time (before flying rather than after). The only time you may put in an additional 'part-cycle' is if you charge the battery then don't use it, so have to discharge to storage voltage, that doesn't happen very often if you can fast charge because you only charge just before flying.

As for charging at high amps. I follow manufacturers recommendations to the letter, they should know what is safe for their batteries... no?.
And the 'risks' of parallel charging?.. What would they be exactly The only real 'risk' is connecting batteries of different cell counts together, and even the most careless among us should be able to avoid that, if not you probably shouldn't be charging Lipo's at all.
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Last edited by JetPlaneFlyer; May 25, 2013 at 11:50 AM.
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Old May 25, 2013, 02:17 PM
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I keep my dozen or so seven year old Lipo batteries stored in the fully charged state. When I get home after flying I recharge. Sometimes a few months go by before I fly again (snow, work, life, etc. get in the way). Never had an issue.
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