Originally Posted by Chap1012

The charging method/math I use is from here:
https://sites.google.com/site/tjingu...arging-how-tos

Very simple. Here I have 3 550mah batteries charging in parallel (note the amp setting).

3X550=1650. Move decimal over 3. = 1.6A

3X750= 2250. Move decimal over 3. = 2.2A

This is for 1C charge rate for parallel charging. Although I admit, I crank it up just a tad at times. For instance, instead of 2.2A on my Rhino's, I may crank it to 2.8A

Mike.

Aha! I caught Mikey charging more than 1C!!! Somebody call the cops!

Welcome to the >1C Club, bro! I love it when I see people relax a bit. HAHAHA YAY!

Good explanation and illustrations, BTW. Cheers.

Originally Posted by Saxguy1000

RAIDEN 3.7V 1300mAh 20C Li-Polymer Battery. This is what I have.

Nice

Originally Posted by stuball56

I don't know any reason why a larger mah battery would be bad for the board. As long as it is a 1s battery it could be a 5,000mah. Wouldnt fly of course, but would not hurt the board. Unless you mean that the increased runtime might overheat the board. That is the only thing I can think of. No matter the capacity of the battery the voltage output is the same. It may be capable of putting out considerably more current, but only if the components demanded it.

Ditto... was just going to say that myself but scrolled a little further and saw your post

Originally Posted by Chap1012

This is for 1C charge rate for parallel charging. Although I admit, I crank it up just a tad at times. For instance, instead of 2.2A on my Rhino's, I may crank it to 2.8AMike.

I nearly always parallel charge between 4 and 6 x 550mah 1s batteries. I will fly them all and then charge them all. When at home this is always at 1C or less but if I charge at the flying field I always charge at 2C. I know that charging at more than 1C reduces the life of the battery but waiting for batteries to charge when at the field reduces my life even further and so I accept the hit!

I think most Lipos will charge at 2C without too much reduction in their life.

Originally Posted by PaulChurchley

I nearly always parallel charge between 4 and 6 x 550mah 1s batteries. I will fly them all and then charge them all. When at home this is always at 1C or less but if I charge at the flying field I always charge at 2C. I know that charging at more than 1C reduces the life of the battery but waiting for batteries to charge when at the field reduces my life even further and so I accept the hit!

I think most Lipos will charge at 2C without too much reduction in their life.

If your battery maker says they charge at greater than 1C, go for it! 1C normally takes me 45 minutes and if I happen to have a slight dent in the casing, there's less chance of problem overheating. That's the way I've seen it. I've never had a battery problem even if if it puffs when using 1C.

Originally Posted by 1Pilgrim

There's no such thing as a free lunch. How much fossil fuel does it take to make a battery? Any mechanical engineer will tell you that a minimum of 70% of the energy is lost each time you convert it from one form to another. The long-term answer is still the same as it was 50 years ago - nuclear power.

I don't dispute that for a second. My point being we can ditch fossil fuels altogether. The UK for example has enough off shore wind resource to power the entire eu and before someone says 'yeah but how do you store it' by hydrogen electrolysis. You then burn it in the same turbines used for natural gas and voila. No co2. Norway gets 80% of it's energy from hydro, France 80% from nuclear. Yes we will have to pay more for energy in the early days but with a globalised economy you only have to look at the progress of computer chips and mobile phones to see the costs would soon plummet as technology gets cheaper and cheaper.

The current situation with lithium batteries is a joke. We mine lithium in south America, then send it to China, then send it back again. Not necessary. Again we will have to suck it up and pay more but the planet is looking pretty screwed. I advise everyone to watch' The age of stupid' just stream it (legally of course, wink wink, Pete postlewaite rip is perfect in it) we really are wasting such a valuable resource burning oil when it's used to make pretty much everything. You might not like Al Gore but as an outsider I can tell you what he says is inconveniently the truth

Sorry for going off topic. I am a Pharm student so know my sciences and will have an answer for every 'but' you have lol. Plus electric motors are more powerful then ic, they have 100% torque at all revs, low maintenance. Plug and play, and fully recyclable from the lithium batteries to the engine itself.

Look up low energy nuclear reactions. Ruined by the name cold fusion. They are real, would cost pennies compared to standard nuclear power plants and by the time hot fusion works it will be too late anyway.

So sorry for going off topic. I'm not a tree hugger just love anything electrical. Mainly for the fact electricity is so easily produced, unbelievably useful and of course makes the rc world super awesome

You can always power that monstrosity with ethanol. I have no issues with that

Originally Posted by grampi

I'll need a charger that can charge several at a time...any suggestions?

I have this one and have been very happy with it. It's only 3A, but that's enough to charge six 500mah batteries at 1C.
http://www.rcgroups.com/forums/showthread.php?t=1785100

Then you'd need the parallel harness like this:
http://www.ebay.com/itm/1-6X-JST-Lip...-/230580978475

Of course, the power comes from a car-type battery. To charge indoors you'd need a power supply like this:
http://www.radioshack.com/product/in...ductId=2103959

Originally Posted by 1Pilgrim

Yes, I remember now - that's why I still have those RKH skids and undercarriage battery mounts laying around.



So where will you "fly" your airboat? Are you anywhere near Alligator Alley?

No, I am far north of Alligator Alley, I am just outside of Jacksonville. One thing about FL. we have water everywhere and marsh lands. It will run on dry grass and at 27cc gas on water it will fly if I let it. I always wanted one, so I figure I would build one. Would work good on snow to. I look at it this way if it is a nasty day I will just get out the Airboat. WS

Originally Posted by 1Pilgrim

My charger will put out the amps, but do I need to worry about balancing the batts?

1st, I don't know squat about electricity.
I thought I read that they should be close before hooking them up to the parallel harness. I'm not sure what "close" means. I've been checking that they're all within .10v (3.8v-3.9v) of each other before connecting them. I think they then balance to each other, like filling an ice cube tray from one spot.
Again, I don't know what I'm talking about, so I blindly go with info. that I dig up on the interweb.
I balance my 2S and 3S batteries before charging so it seems I should for charging multiple 1S as well.

Originally Posted by Wind Spirit

I have one of those as well but you still have to fight with the canopy and I did not want to cut the canopy. That is why I like my mount under center of my bird. WS

Battery mounts.WS

I completely forgot about this charger I have that I used to charge the batteries for my Edge 540:

http://www.rcgroups.com/forums/showthread.php?t=551237

Will it work for charging the 120 batteries? It should. Because of the way the plugs are set up on this charger, I would either have to get an adapter that parallels the 1 cell output into 4 connectors, which would only give me .5 amps of charging power if charging 4 batteries at a time (because each charging output maxes out at 2 amps), or I would have to adapt the 2, 3, and 4 cell outputs to a 1 cell output, then I would have 2 amps available for each of the 4 outputs. Do any of you know where I could get the adapters I need? I suppose it wouldn't be difficult to make the adapters either, I'd just have to pick up a 2, 3, and 4 cell plug and wire it for 1 cell, then put a 1 cell connector on the other end. I'd just have to find out where to buy the plugs and the pins that go in them.

Originally Posted by grampi

Will it work for charging the 120 batteries?

Yes. With a cable that fits the 120SR battery.

That charger will charge any Lipo that is 1S - 4S at up to 2A.

With the right parallel charging cable you could charge up to 4 standard 120SR batteries (4 x 500mah) in parallel at the same time at 1C.

Originally Posted by grampi

I have this charger...

No jacks for banana plugs ? I don't know if you'll find a harness with that type of male end. Of course, you could solder one on.

Guys, for 40 bucks you can't go wrong with the Thunder AC6. I puts out 5amps. Plugs into A/C wall. With the right cables "I think" it can be taken in the field. I never tried it. This was the charger highly recommended by veteran hobbyist here on RCG. I can charge up to 3, 1300mah batts in parallel. Remember? 3 X 1300 = 3900. Move decimal over 3 and you get 3.9 amps charge rate at 1C. Think of the 1S 550mah batts you'll be able to charge

http://www.hobbypartz.com/thac6smbachw.html

Here's my favorite link I like to though out on battery management. Quite easy to read and understand. Get used to it

https://sites.google.com/site/tjingu...arging-how-tos
To be honest with you all, I'm beginning to think you guys are not even opening this link, reading it, and then put it in faves. To this day, I still refer to it

Mike.

Heli Pad, It looks like you caught me red handed Like Sax was saying, if the manufacturer claims it can be charged at a higher rate...go for it. But this should also be taken with a grain of salt. You know how some battery companies will tout how great their batteries are....right?

Mike.

Originally Posted by Brian VT

No jacks for banana plugs ? I don't know if you'll find a harness with that type of male end. Of course, you could solder one on.

The batteries for the 120 a 1 cell, right? So if no one makes these adapter cables, how difficult could it be to get a 2 cell, 3 cell and 4 cell connectors to fit the output plugs on the charger, then just install 2 wires (one + and one -) as the output polarity is marked on each output, then just install the 1 cell connetor on the other end. These plugs are common and should be easy to find if one is looking in the right places. Someone's got to know where stuff like these plugs, and the pins that go in them are sold.