fake BMS in knockoff tool batteries - Page 1
Forum section: electronics / general

author: NiHaoMike
author_rank: Super Contributor
timestamp: December 30, 2023, 02:50:13 pm
content: Perhaps the solution is to have the casing be transparent so that such dangerous cost cutting would be easier to spot?

author: tszaboo
author_rank: Super Contributor
timestamp: December 30, 2023, 04:05:57 pm
content: Quote from: NiHaoMike on December 30, 2023, 02:50:13 pmIn the EU it's illegal to sell dangerous parts with CE marking.They just need to make battery packs as part of the mandatory third party certification instead of self declaration.

author: madires
author_rank: Super Contributor
timestamp: December 30, 2023, 04:09:50 pm
content: That's really bad and dangerous, but not surprising. I'd guess the 16850s are also cheap junk.

author: Kleinstein
author_rank: Super Contributor
timestamp: December 30, 2023, 05:41:59 pm
content: The original Makita battery packs also don't have that much more supervision and no balancing. The ones I opened just checked one more voltage in the center (so groups of 2 and 3 cells in series. So they can tell if the cells go much out of balance and mark the pack as bad or tell the machine/ charger to stop, but that is about it. Another important function they have is to have a temperature sensor and signal if they are too hot.

author: AVGresponding
author_rank: Super Contributor
timestamp: December 30, 2023, 09:05:27 pm
content: Quote from: tszaboo on December 30, 2023, 04:05:57 pmProblem with that is, unless someone complains, the chances of it being checked are negligible.

author: tszaboo
author_rank: Super Contributor
timestamp: December 30, 2023, 09:48:33 pm
content: Quote from: AVGresponding on December 30, 2023, 09:05:27 pmThey would check the documentation on the yearly ISO9001 review.

author: AVGresponding
author_rank: Super Contributor
timestamp: December 31, 2023, 01:49:35 pm
content: Quote from: tszaboo on December 30, 2023, 09:48:33 pmI'm sceptical that third party vendors on the likes of ebay, Amazon, and AliX sell items that genuinely comply withanystandards. The best you could hope for is to get bricks and mortar outfits like Screwfix, Aldi, (insert local discount/hardware store of choice here), to comply, which they probably already do anyway.

author: Helio_Centra
author_rank: Regular Contributor
timestamp: January 08, 2024, 05:41:54 pm
content: The white wires are only a temperature sensor. Who knows if that works?I would be interested in a breakdown of what the circuit board actually does if not actual BMS things.

author: Spar59
author_rank: Contributor
timestamp: January 15, 2024, 05:09:54 pm
content: Unfortunately dodgy manufacturers have no issues about putting fake approvals marks on their products, I bought an outdoor encapsulated power supply from Amazon that had cable core colours that do not conform to EEC standards despite its CE compliance mark, and also equipment with fake or non-existent fuses in their UK standard plug.

author: robint
author_rank: Regular Contributor
timestamp: January 22, 2024, 06:16:22 pm
content: BigCliveDotCom does a tremendous job deconstructing all the rubbish from PRC and some of it si really dangerous. Beware of mains garden lighting with metal casings, floodlight etc. He found them with no earth wire and sometimes a green earth wire from the cable not connected to anything. Go figure, just dont let the kids or pets near any of it.

author: thm_w
author_rank: Super Contributor
timestamp: January 23, 2024, 01:09:50 am
content: Quote from: Kleinstein on December 30, 2023, 05:41:59 pmYeah this is similar to an original older Makita BMS, you can see some photos here (they removed all of the components though):https://broncosis.blogspot.com/2010/01/my-intro-well-to-start-of-i-guess-i.htmlYou can find the board used in the video here:https://www.lithiumbatterypcb.com/product/bl1440-bl1430-bl1415-serial-pcb-board-for-14-4v-makita-pcb-board/seems like a legit company. Though she said the cell reached 4.5V, so not sure... maybe it did cut out at that 4.5V point or the multimeter is not accurate enough.I wouldn't buy those packs of course. Aliexpress has some decent BMS replacements, which should be much better than these "old style" ones (for cases where the BMS has been locked out but the batteries are still good):https://www.aliexpress.us/item/3256803132573208.htmlhttps://www.aliexpress.us/item/3256805027980101.html