A123 Batteries for Dummies.

[drewbags]

	Quote: Originally Posted by Kevin B
	My average is like drewbags, are you saying we have problems? I gotta say guys, I think I am starting to regret buying the A123s... I can't tell if my plane is safe to fly or not. It has been a real joy to fly for the first 7 flights. Total usage is 471. Divide that by 2 packs and the total is 235.5.

Kevin

With numbers like that I would chill and enjoy - looks normal to me.

[Kevin B]

Tom, the numbers may have been misread... 3 total fights, pack one used .706, pack 2 used .707. Total used 1.413 divided by three flights .471. Divided by 2 packs .2355. I think this is what I posted in the first numbers post...


Anyway, I will continue to track the numbers and post more.

[Kevin B]

Okay, new numbers for the last 3 flights. Almost identical to the previous three flights.
Pack 1 amount used .725. Pack 2 amount used .718. Total used for 3 flights 1.443. Divided by 3 flights is .481 per flight, .240 per pack per flight. I have ordered an e-flight power meter to check the voltage and binding.

The snip I uploaded shows the chart I am keeping. The last charge date is tonight. Seems usage is increasing....

I am beginning to wonder if my tailwheel springs are too tight, I am starting to use the rudder more and more each flight. The three flights tonight I was working out the rudder aileron mixing to get rid of some coupling.

[tonyc9075]

Black & Decker VPX battery – 40% Laser test flight.

I did a shake down test flight on a 40% Laser using two Black & Decker VPX battery packs. The Laser is light weight and uses 5 digital servo’s to control flight and one on throttle. The first flight for this new airplane was a gentle 12 minute, take off, some loops some rolls and some turns and one landing. So there was not a lot of stick banging. The reason for the gentle flight is new scratch built airplane, new servo’s, and new battery packs, this was a first time A123 experience for me.

The two packs started out at 6.9 volts each. They were both 100% charged the night before and were used some to set up the airplane for first flight. Control service adjustments and testing used some amount of power. The 6.9 volts was just as I was ready to fly.

After I recharged using the CellPro 4 the amount I put back in was .061 in one and .049 in the second battery. Recharge took all of 5 minutes. Not much power usage at this point. I could fly about a dozen flights at the gentle level and not recharge.

[cdallen]

Will be new to gas soon. Want to use dual A123 batts for rx and single for Ign. What is the best set up, swithch wise etc. Do you have a system where you take the battery out for charging or leave it in? Best switch for failsafe etc.

[sprice50]

	Quote: Originally Posted by Kevin B
	Tom, the numbers may have been misread... 3 total fights, pack one used .706, pack 2 used .707. Total used 1.413 divided by three flights .471. Divided by 2 packs .2355. I think this is what I posted in the first numbers post... Anyway, I will continue to track the numbers and post more.

Another factor is length of average flights? What is yours?

[Kevin B]

Between 12 and 15 minutes.

[toti_ducati]

im a real A123 newbie , i got tired of charging nicads on my 110 EF Yak every 2.5 flights, I decided to switch to |A123s, now I have 2 sets of 2300s thru a fromeco wolverine switch then thru a powerexpander sport, from what I understand reading the posts here is.
1) once they are balanced I can just charge thru the wolverine but at like less than 3 amps because thats the max the JR plug can take?
2) I also soldered an extra deans plug direct to A123 battery so I can fast charge them on the plane up to 5 amps? and since they dont blow its safe to have them on the plane?
3) the easiest way to charge them would be to leave them on the plane and charge balance them by using wire extentions hanging from the plane, and just to make sure that the switches are off when I charge?
4) since the condition of each cell can be checked when balancing, it would be safe to use just a single 2300 with 2 leads for 2 switches on my 50cc?

I hope I got this right cuz this is what I did, will fly this weekend and enjoy a chargeless day

[dick hanson]

	Quote: Originally Posted by toti_ducati
	im a real A123 newbie , i got tired of charging nicads on my 110 EF Yak every 2.5 flights, I decided to switch to |A123s, now I have 2 sets of 2300s thru a fromeco wolverine switch then thru a powerexpander sport, from what I understand reading the posts here is. 1) once they are balanced I can just charge thru the wolverine but at like less than 3 amps because thats the max the JR plug can take? 2) I also soldered an extra deans plug direct to A123 battery so I can fast charge them on the plane up to 5 amps? and since they dont blow its safe to have them on the plane? 3) the easiest way to charge them would be to leave them on the plane and charge balance them by using wire extentions hanging from the plane, and just to make sure that the switches are off when I charge? 4) since the condition of each cell can be checked when balancing, it would be safe to use just a single 2300 with 2 leads for 2 switches on my 50cc? I hope I got this right cuz this is what I did, will fly this weekend and enjoy a chargeless day

1-- yes
2--yes
3--no - disconnect one pack the switches typically do not disconnect all wires.
4 yes - or use 2, individual, 1100 ma A123
50 cc don't require all the big servos multiple packs etc., waste of money and adds weight.

[Panzlflyer]

Yes, to all if you only use one charger at a time, I do it on all my setups with a Wolverine...It aint no Jr switch and isolates one from the other.
Its a good idea to disconnect the switch if leaving it for a long time as it pulls a small amount out of the pack in the off position.

[drewbags]

Out of interest I have tried charging mine at 5A through a standard JR plug with no problems. Whether my charger actually charges at 5A I don't know but it hasn't gone bang yet!!

[dick hanson]

	Quote: Originally Posted by drewbags
	Out of interest I have tried charging mine at 5A through a standard JR plug with no problems. Whether my charger actually charges at 5A I don't know but it hasn't gone bang yet!!

A steady 4 amps will really warm the HD JR connectors
The non HD or aftermarket plugs will sometimes overheat and distort at a steady 4 amps - in one minute.
Nothing explodes but the plastic surrounding the crimped connections can badly soften and distort -some connectors . Most plugs are rated at 3 amps .
The momentary loads can be higher . There are NO crimped setups available which permit higher amperage
the little do it yerself ones are even worse.
A real do it yourselfer - can swap all of it to new large wires throughout the entire system and use Deans, 3 pin mini polarized plugs

too much work for me -I just use HD genuine HD stuff -and make sure all connections feel snug.