RC battery

[centax]

I've got this battery from an RC plane I don't ever use I was wondering if it'd be possible to use it to power a passthru.

 

[beast775]

i dont see why not.ive got an old electric bicycle pack,i might open up one day,just give it a try if you have a charger.those look like c cells.there very good with high drain nimh cells.

 

[bigblue30]

I've got this battery from an RC plane I don't ever use I was wondering if it'd be possible to use it to power a passthru.

View attachment 10361

Centax,
I hope you are talking about using just some of the batteries in that pack...They look like NI-HM (nickel-metal hydride cells). Each one in there is 1.2 volts. You have (6) 1.2 volt batteries there.

If you just hook the up to a PT that does not have a battery in it, you will hit your atty with 7.2 volts.......that would be a heck of a hit for a short time before your atty burns out.

If it has a built in battery.....most of them want to be plugged into 5 volts.
This "could" blow that battery.

Now if you just use 3....3 X 1.2 = 3.6... then that would work.
or use 4....4 X 1.2 = 4.8.... that would also work.

Problem with just using 3 or 4 is that you can no longer use the charger that you use when it was a 7.2 volt pack. you will need to get a new charger or mod the one you have.

 

[centax]

Ok I wasn't planning on doing anything to the battery just splicing a female connecter to a passthru with no battery. But if it's gonna blow the atty nevermind. What if I used a HV atty or maybe an old atty whose resistence has gone up?

 

[bigblue30]

I know I am going to sound like a complete geek....but its the only way I know to explain it...sorry in advance.

Lets look at an e-cig battery setup..you have a battery putting out about 3.7 volts what an atty of around 3 ohms some are lower(LR) and some are higher(HR). 3.7 volts with an 3 ohm atty would be around 4.5 watts (or heat) that the atty is making. Around 4-5 watts as good for most attys.

I good way think about what 4-5 watts are, think about a 7 watt night light. Your atty was designed to make just a little less heat then a night light.

Now you plug it into a true 5 volt passthrough....5 volts with the same atty = 8.3 watts. This is why you get a better "hit", but can shorten the life of your atty.

Now for the big one....7.2 volts in to 3 ohm atty...17.2 watts. Do you see why I said before that the "hit" would be great for a very short time?

You asked if a HR atty would help....To get 7.2 volts back down to the "safe" 5 watts you would need a atty with a resistance of almost 10.5 ohms.

I do not know of any that high.

Again ..sorry if I got tooooo geeky.

Steve

 

[roadrash]

Ok I wasn't planning on doing anything to the battery just splicing a female connecter to a passthru with no battery. But if it's gonna blow the atty nevermind. What if I used a HV atty or maybe an old atty whose resistence has gone up?

give it a shot on a under performing Attie, I run some at 7v to 8v. The only way it will work. 9v works but taste real nasty, seems to burn the juice.
After you run at 7v, put it back to 3.7v or 5v. some times the higher voltage may burn of the crud and give your attie a new life.

 

[WillyB]

Ok I wasn't planning on doing anything to the battery just splicing a female connecter to a passthru with no battery. But if it's gonna blow the atty nevermind. What if I used a HV atty or maybe an old atty whose resistence has gone up?

Just splice this in between the pack to your female connector (USB I guess?).

UCC383T-5 Texas Instruments Low Dropout (LDO) Regulators

It will work without any other components and will provide a constant 5V till the pack drops below 5.5V.