maillemaker

Hi all,

What do you recommend for a replacement 7.4V battery for a Heng Long PIII?

Thanks,
Steve

Rad_Schuhart

The biggest 2S lipo that you can fit inside.

Im using a 5.600 mah. Gives me hours of non stop running.

maillemaker

Thanks, I did some searching for 7.4V battery on Amazon but could not find any with the right connections.

Anyone have a link?

Steve

Rad_Schuhart

Well, first of all I would not buy a battery in amazon. Instead go to hobbyking, introduce the dimensions of the battery you want, and choose the one that suits you most.

As far as I remember heng long uses the old tamiya conectors...Those are know for being very bad and old connectors and the popularity of them is at the bottom of the ocean right now... So Id choose a battery with XT60 connectors. Deans if you want something smaller. Both of them are very easy to solder, and no need of any crimping tool.

maillemaker

I'm really just looking for a drop-in replacement. Googling indicates this is hard to do.

Steve

Perry S.

Lipos will need a different controller because they require low voltage cutoff to keep them safe. I guess you could use the HL controller if you installed an inline low voltage battery cuttoff. If you want a straight drop with the same connector you should stick with a high quality NiMH battery. I had a Traxxas one that I wasn't using and soldered on the Futaba connector that HL uses.

maillemaker

Does no one sell a direct replacement?

Steve

MAUS45

These will work, 7.2v is ok for the Panzer III. They have the Tamiya connector as well.
https://www.ebay.com/i/122550908478?chn=ps

Perry S.

7.2V NiMH are ubiquitous and available everywhere. They are a direct drop in replacement.

https://www.amazon.com/s/ref=nb_sb_n...A7.2+volt+nimh

I am not aware of 7.4V NiMH packs as that is a standard Lipo voltage. I am not aware of any Lipos with the HL Futaba style connector.

Dusty Steppes

I would not recommend using a tamiya style connector on a lipo battery. They are a crimp type connector that are only rated for 15 amps and are prone to mechanical failure.

But if you insist on using that type of connector you could try contacting Maxpacks. You can choose the type of connector you want.

https://www.maxxpacks.com/

Perry S.

Please do listen to my advice though and think twice about running a Lipo into the HL electronics without some sort of low voltage cutoff if you have to have a Lipo.

Dusty Steppes

^^^^^
This!

Personally, I would get a good NiMh.
​​​​​​

maillemaker

The P3 has a strangely-shaped battery box with a "step" in it. So only the little 2-cell battery it came with fits in it, not the usual 7.2V bricks.

So, since I have 3 of the 7.2V bricks (NiMH, NiCD) I carved open the P3 battery box so I can fit a standard-sized battery in it. I figured 7.2V would work fine in a 7.4V system.

But with a full charge the tank would only run a couple of minutes before it bogged down and stopped running. It has no smoke or sound so the only thing running are the motors and receiver.

Did the tank come with a LiPo battery? Did it come with a low-voltage cutoff?

Steve

Perry S.

My Heng Long PIII came with the standard NiMH 6 cell pack. Maybe post a pic of what you have. If the battery is decent quality it should run a half hour maybe more.

maillemaker

This is the battery that came with my Heng Long PIII:



I don't have a picture of the battery compartment handy, but it has a "step" in it, so that a standard 6-cell pack will not fit in it. I cut the step away to put a 7.2V 6-cell pack in it but it only runs about 3 minutes before dying. I'll try another 6-cell pack.

Steve

Perry S.

hmmmm,
That is a Lipo.
I think I understand what is going on here. I bought my PIII years ago and it came with the standard 6 cell NiMH pack. In fact they came with Nicads way back then.
It looks like you have a recent PIII version with the new 2.4 GHz electronics and those do use a Lipo according to the Mato site. It is a 1.8Ahr - 7.4V which seems pretty small to me.
I wouldn't have guessed it without seeing the pic. Maybe someone with more experience on the HL 2.4 GHz system can comment.

maillemaker

Nope, it's an archaic system that predates crystals. It has an ABC channel selection on the controller and the tank. It's before RX18 even. It has no smoke and no sound.

Steve

Perry S.

Man, I am confused as to what you have then. I don't know where you bought it and who would sell that configuration. Non S&S electronics from 5+ years ago mated to a Lipo battery. What is this craziness?