Matador
100 kW
- Joined
- Jun 29, 2016
- Messages
- 1,045
Last year, I got myself a BBSHD 1000W kit. In the process of building a 14S battery, I search for a good BMS. I finally ordered 2 BMS (minimum order quantity) from BestTech Power in China, as people said they were good quality. But with shipping, costums, local taxes and exchange rate, it ended up costing me 240 canadian dollars for the two pieces. Yikes !!! In the process of wiring the BMS top a 14S9P I assembled in august 2016, I did something wrong. I think I connected a certain balance lead in a wrong place, and in less than a second, I smelled the magic blue smoke (as they say) :wink: . Anyway, I did the second BMS wiring good and it worked, but that 120 dollars gone in smoke left me a bitter taste even though it was clearly my fault (lesson learned).
The BMS model is a good one to : HCX-D131 from BesTech Power :
14S Li-Ion
Rated 80A continuous, 200A peak discharge
20A charge
Balance current is on the High Side for a BMS (168 mA per string).
Balance @ 4.20V
LVC : 3.00V ; HVC : 4.28 V
Here’s the datasheet of the HCX-D131 80A 14S Li-Ion : View attachment 分口 14S D131 Li-ion BesTech Power datasheet.pdf
So I thought why not examine the thing, try to identify components, and REPAIR IT…. No, I’m not looking for a bottle of magic blue smoke , but a little help from you kind folks of the endless sphere would be very appreciated. At the same time, this post is also a contribution to the whole community, I did put in my best effort to take pictures or photomicrographs of every component I could find. I just don’t know what the codes mean…. So I’m kind of stuck…
Anyways, If you recognise a component of this BMS from the picture, please post the answer here. Even better if you find de datasheet of the component and post the link. Or if you just have some general comments. I figured, many people here buy BMSs from BesTech Power, so documenting the components might help other people fix their electronics if they have similar issures.
This, is an autopsy examination of the BesTech Power 14S Li-Ion, 80A HCX-D131 BMS. I will start with general gross pictures, then go ahead with microscopic examination ( I took my old microscope, and my IPod touch to take pictures, photoshoped everything, and made drawings).
Goals here : 1 - Sharing knowledge. 2 – Find a way to repair this BMS (I identified 3 fried components under the scope, one of which I have no clue what it does), 3 – Share discussion so we can all contribute to identify every components here (I NUMBERED THEM FOR EASE OF RECALLING).
GROSS EXAMINATION :
The good, the bad, and the ugly :
My dead HCX-D131 : Nothing seems wrong visually yet...
After splitting in halves (the clamshell approach) we can see :
The outer surfaces : still looks okay
Revealing the MosFETs
View attachment 14
All looking good. Closeup :
Clamshell approach, Inside side : View attachment 11
Close inspection :
TIME FOR SOME X-RAYS NOW :
View attachment 6
Well then, time to pull out the scope, get ready for some serious MICROMAPPING :
Please see next one of my post down here.
Matador
The BMS model is a good one to : HCX-D131 from BesTech Power :
14S Li-Ion
Rated 80A continuous, 200A peak discharge
20A charge
Balance current is on the High Side for a BMS (168 mA per string).
Balance @ 4.20V
LVC : 3.00V ; HVC : 4.28 V
Here’s the datasheet of the HCX-D131 80A 14S Li-Ion : View attachment 分口 14S D131 Li-ion BesTech Power datasheet.pdf
So I thought why not examine the thing, try to identify components, and REPAIR IT…. No, I’m not looking for a bottle of magic blue smoke , but a little help from you kind folks of the endless sphere would be very appreciated. At the same time, this post is also a contribution to the whole community, I did put in my best effort to take pictures or photomicrographs of every component I could find. I just don’t know what the codes mean…. So I’m kind of stuck…
Anyways, If you recognise a component of this BMS from the picture, please post the answer here. Even better if you find de datasheet of the component and post the link. Or if you just have some general comments. I figured, many people here buy BMSs from BesTech Power, so documenting the components might help other people fix their electronics if they have similar issures.
This, is an autopsy examination of the BesTech Power 14S Li-Ion, 80A HCX-D131 BMS. I will start with general gross pictures, then go ahead with microscopic examination ( I took my old microscope, and my IPod touch to take pictures, photoshoped everything, and made drawings).
Goals here : 1 - Sharing knowledge. 2 – Find a way to repair this BMS (I identified 3 fried components under the scope, one of which I have no clue what it does), 3 – Share discussion so we can all contribute to identify every components here (I NUMBERED THEM FOR EASE OF RECALLING).
GROSS EXAMINATION :
The good, the bad, and the ugly :
My dead HCX-D131 : Nothing seems wrong visually yet...
After splitting in halves (the clamshell approach) we can see :
The outer surfaces : still looks okay
Revealing the MosFETs
View attachment 14
All looking good. Closeup :
Clamshell approach, Inside side : View attachment 11
Close inspection :
TIME FOR SOME X-RAYS NOW :
View attachment 6
Well then, time to pull out the scope, get ready for some serious MICROMAPPING :
Please see next one of my post down here.
Matador