Originally Posted by
Roelof
You can always cut off the connector with some wire from the old battery and solder it to the new one.
I know but I didn't want to do that in case I ever wanted to go back to the OEM pack. Plus, it's been bugging me for a long time that the connector was not specified. You can find pigtails from various vendors but the the actuall connector is usually called something generic like Spektrum/JR Tx connector. I figured it had to be an actual connector. After considerable digging, I have identified the connector. It a JST EH (not XH or PH). Here is a link to the connector on the JST site
https://www.jst.com/products/crimp-s.../eh-connector/
The Actual part number for the plug housing is
EHR-2
but them you also need pins and a crimper
The part is listed on Digikey but they don't have stock.
https://www.digikey.com/en/products/...c/EHR-2/527224
All you really need to make a pack is a pigtail. I found these on Amazon
Radicalrc also sells the pigtail but doesn't tell you the connector is JST EH
https://www.radicalrc.com/item/2-Pol...m-White-100494
I bought both and they both fit.
To make a battery pack, I decided to use Li Ion 14500. The 14500 is the same size as a regular AA. So four will fit. However, the Li Ion battery is about twice the votage of an standard AA so I wired them in 2P2S: two pairs of batteries in parallel with the pairs in series. This gives a 2S pack, 8.2V fully charged. Various places sell 14500 batteries but a lot of them seemed low in capacity. Most are around 800mAh. A pair in parallel would have a capacity of 1600mAh. That is probably fine but the OEM pack has a capacity of 2400mAh. So I looked around more. There was one on Amazon listed as 2500mAh
but the reviews all said the capacity was a gross exaggeration. In the end, I bought these that are listed as 1500mAh,
https://www.18650batterystore.com/pr...mah-3a-battery
so a 2S pack built as 2S2P would have a capacity of 3000mAh. Not sure how true that is without testing them which I will probably do just to know one way or the other. Here is a photo of the final pack connected to the DX4S. I also added a 2S balance plug.
battery pack with 14500 Li Ion batteries in 2S2P, JST EH power connector and standard 2S balance plug