Hailong Battery - change 5-pin to 4-pin connector


New member
Local time
8:39 PM
May 26, 2023
Canberra, Australia
I'm a newbie here, I have searched this forum and others to no avail. I did find a YouTube video on the subject which was pretty useless.

I converted my gravel bike using a 36V 250W Tong Sheng kit using a Hailong 36V battery. It works great and no issues for two years.
My neighbour was so impressed he did the same thing with his road bike. But last month he had car accident and won't be able to ride again so I bought his converted bike. I figured it would be great having a second battery for use with either bike on longer trips.

Then I realised his Hailong battery has a 5-blade connector while mine has 4-blade. Its like computing - you can pick and choose which standards you want to use.

Some research indicates it is possible to change connectors and these are available, but little advice as to how to do this. So my questions are has anyone done this? how is it done? is it the male connector on the battery that is changed or the female connector on the base? are there any limitations on type of battery case that can be converted as there seem to be some superficial differences? will the converted battery / base be compatible- it looks like it but can't be sure?.
Hopefully someone can help

I could sell one battery and by another that is compatible, but that sounds a bit defeatist.
Although this question is long-dead, it deserves an answer for someone searching on this topic.

Yes, it is possible to buy a Hailong battery case and the 4/5 pin base for it to slide into.
You can convert a 5 pin Hailong to a 4 pin Hailong battery base by buying an empty from one of the Chinese
Alibaba, Aliexpress, (and similar) sites. You open the case, and move the batteries and battery management board from your old case
and transplant it to the new case. Make sure the new case has the right hole for the type of charger the old case used.
i.e. Typically (but not always) a barrel connector.

As of 22 October 2023 a new case and base plate runs about 10 to 28 US dollars.
You can also get one from Amazon for about 65 US dollars.
You will need a soldering iron and solder to perform the transplant of the guts.

I considered doing this recently, so this topic was researched.
Below is an example of an AlieExpress listing. Ten Bucks plus shipping.


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