Faulty Bosch 18V ProCore Battery - Issues, Diagnose & Repair 

I enjoyed how thorough and correct this video was. It would be interesting to see an alternative version of this video for people who only have basic tools - voltmeter, hacksaw, soldering iron.

Fantastic tips, dude! Thanks! 😊 I have a ToolKitRC M6 and it's great! Happy new year! And stay safe there with your family! 🖖😊

Great video. Thanks for the useful info on the Bosch battery packs.

happy new year

the samsung 40T has major issue failure version 1 and 2 so far version 3 needed to wait and see great video Kwelder is releasing a copper welder version

Very good video. Everything done very well.

You can pull the tabs off without the ball grinder. But your way they come off flatter which is a nice bonus. 2:40 Heat the red housing and it will more easily let go of the cells. Same before re-inserting cells. Better not rotate the cells when inserting or you might damage the balance contacts. 4:33 I have the same spot welder and I can weld those copper tabs just fine. 6:00 Wow, that is a nice charger. Aren't you afraid the new cells combined with the older cells remaining in the pack will soon give issues? I tend to replace all at once. The Bosch battery itself doesn't do balancing, only monitoring.

Thank you for the very detailed video. After going through my battery, I found that it has full voltage )18.4v) and each cell reads 4.7v. But it will not power my cordless vacuum nor does any lights blink on the charger when plugged in. The front battery capacity LED do not light up either. Any ideas on this one?

Ok, fantástico trabajo.👍🤓😜

I love that they use 0.3mm copper, all the other manufacturers slap the cheapest and easiest to solder strips that they can find(nickel-platted steel) and call it a day.

Cool!!! Bravo!!! Good tip. /// Хороший совет! Отличный ремонт!

Good techniques, and I have a few duds I need to sort, 😀

I really like how you explain all the process! But, how can i balance the cells without a fancy charger like this?

You're Genious 😊

the balancing interests me. Like all poles were connected, how does it supply charge to an individual cell? wouldn't all current just spread out over all poles?

The reason the contacts are copper is for heat transfer. Removing the would make the battery bot perform as well.

Can someone recommend a replacement bms board for those batteries? I have the older lithium batteries

I didn't have a charger with BMC, so I balanced the cell with a 12V car lamp. It was painly boring, but I managed to succeed.

The balancing step was not needed. If you put the battery in the Bosch charger with the cells exposed and monitored the individual cell voltage you will see the Bosch charger actually balances the cells itself.

You can do that on older batteries not on newer.On newer electronic board will lock when cell are dead or disconnected from cells.

What would happen if after replacing start charging without balancing?

These ProCore batteries seem to be crap. I got one on my bench now that had done the exact same thing; drained two cells to 0 volts! How can the BMS or tool even allow voltage to drop that far?

Wow, nice but a steep learning curve as a electro noob 😂. Do you think it is possible to create only one charger for multiple 18V battery technology? In stead of having 6 different brands.

Good tip 🔵🔵🔵🙂🙂🙂👍👍👍🔵🔵🔵

we watched how a quality work is done

you left 3 old cells and installed 2 new cells / you think they have same capacity? Soon the battery will get out of balance and then you will need to balance again. Next time replace all cells

Mmm, apply too much heat because say as in my case I suck at soldering and I have trouble attaching the "balancing" wires. I can wreck the good (and new batteries) or I cause a 💥, injure myself and burn my house down. When showing people how to "repair" a potentially explosive device, might be a good idea to stick to the benign topics like how to make hidden alcohol storage containers with none exploding PVC. Just don't set fire to it unless you have a gas mask that'll filter out the _not so healthy_ chlorine gas. Have a good one. 👍😁

only if some of the cells aren't fryed like that

use bench power supply man

It will die quickly because you didn't replaced all the cells

What you did is dangerous and it will not survive for very long. A lithium battery works between 2.5 and 4.2V. You can't go higher or lower than these voltages unless you want an explosion. So, when you make a series pack consisting of more than one of these batteries, you can't separate them easily, so you charge them together. To charge them together, their capacities must match to a tolerance of around 100mah. If it doesn't, then lower capacity ones will drain faster than higher ones and once low capacity cells deplete, the protection circuitry will turn the output off. Now you have 3 depleted cells and 2 cells at 25% state of charge. Over each cycle this difference will be cumulative, meaning the difference will grow larger after every cycle until something stops working or blows up. New cells will have higher capacity and the on board tiny balancing circuit will not be able to balance such a large capacity gap. Virtually all drills include a passive balancing circuit, which start working at around 4.1V. At that point it will stop charging and discharge higher voltage cells through a small resistor to balance them. That resistor dissipates the charge as heat but since they are very small, they can't dissipate much heat. That means they draw a small amount of current, usually 500mA or 1A in order to keep heat under control. So, since your new cells will have 5Ah and your old cells may have 3. 5Ah left in them, the balancer needs to work for many hours to balance them, which will get out of balance again during top charging to 4.2V. What will make it worse is the fact that you might, for various reasons, cut the charge before full, which will only exacerbate the problem.