C3 Battery Tear Down, Part 1a скачать в хорошем качестве

C3 Battery Tear Down, Part 1a

Time to tear apart one of my dead C3 Lithium-Ion battery packs to see what is inside and perhaps see what is wrong with it. I re-edited this video to speed up the screw removal sequence after I figured out how to do that in Movie Maker Live. Let me know if you like the sped up video. Other than that it is the same video as Part 1. First step is to round up a T-10 security Torx bit to remove the 4 screws. Then pop off the top to reveal the battery management system (BMS) and the 18650 cells underneath. The BMS in these C3 packs looks very sophisticated. I'll try to highlight some of the features over the course of a few upcoming videos as well as what you saw in the earlier Fuel Gauge video. Testing cell voltage, it appears that the #2 and #3 cells are dead, measuring 0.0 volts. Could be bad connections or solder joints, so I'll test that out at a later time. At the end are a few close-up shots of the BMS, which appears to be quite advanced. It is mostly surface mount technology with a pair of high current FETs to handle the low and high voltage disconnect function. I opened a second pack and the BMS looks a little different, so I'll try to post a video later about the different version. I'll also try to get some better close-up images to see if we can discern any part numbers. The two defective packs I have tested both show well less than 15V (3V/cell), so for a cursory test, put a meter across the +/- terminals and check the voltage if you are checking used batteries. If over 15V, likely the pack just needs a charge. If less than 15V, it'll need to be torn apart for further testing. I got two of each in my batch of 4 "dead" packs. All in all, I was quite blown away by the BMS board, I was not expecting anything that elaborate in there. In the Black and Decker NiCad pack that I tore apart, there were just the cells and interconnect wiring. So over following videos in this series, I'll see what I can tease out of the BMS as far as its functionality and also try to get some data on the battery pack. On the bottom of the pack, a 24 watt-hour capacity is listed along with 19.2 volts. So stay tuned for updates as I dig into how these battery packs work and how to fix a couple of different issues. Thanks for watching!