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

[@aliancemd]

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.

[@vernehenzel]

Some of the Bosch battery housings (like the one I bought in 2021, which failed in 2024) are put together with screws like in this video. I had trouble taking it apart until I realized that one of the screws is covered with a plastic plug. Just dig into the hole with a screwdriver until you make contact with the screw head and it will come out like all the others.

[@321tryagain]

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.

[@jcvjcvjcvjcv]

No that would not be nice, as it would result in half ruined pack straight from the repair.

[@TranTek]

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

[@MCsCreations]

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

[@chriscole1859]

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

[@Arek_R.]

LI-ON battery pack factories building packs for example of 40 cells will discard entire assembly if there's one bad weld. Those are being then handed over to recycling company. Someone at the recycling company takes them and then disassembles those for sale instead of recycling those. Much greener than just grinding those unused cells to raw materials.

[@aquakey9834]

Very green but also very illegal, these recycling coys r paid to dispose of these not break them up and resell them for profit. Its the same for every other electronic goods, it brings deflected goods into the market bearing the manufacturer's name

[@taaviplaan]

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

[@azman4749]

If all need to change, better buy new pack batteries.

[@PhilippStadler]

@@azman4749 individual batteries are still way cheaper than a new pack

[@chris_hertford]

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.

[@eliasjoserodriguez5160]

Thats Very cool that makes repairs more easier

[@jcvjcvjcvjcv]

Even Bosch itself says... no balancing.

[@hericar]

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

[@jcvjcvjcvjcv]

One by one with bench power supply or regular charger for lithium cells. He said that in the video, but it takes more time and since he had this tool, he used this.

[@donalexey]

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.

[@PhilippStadler]

How can you balance cells that are put into series? You need to address each individual cell

[@donalexey]

@@PhilippStadler You have to open battery case to do it.

[@womacko]

Great and solid video :)

[@ijjyahmed2001]

Very good video. Everything done very well.

[@LinusJohansson-yu7cy]

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?

[@jcvjcvjcvjcv]

Bosch has a bunch of tools that don't respect the 'battery = empty' signal and keep on draining it. Pretty much all the connected stuff does that. The BMS itself does not disconnect either terminal. It signals on one of the three middle poles.

[@Krishell]

Happens to 6 of mine. I hate them. Just googled it now. Happens to everyone.

[@ВилиамРит]

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

[@mikecrane2782]

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

[@ealneas1]

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

[@dusanmilojevic3017]

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

[@mohamedelkady6237]

Depends on the pack, this a recent Bosch pack, looks like it doesn’t lock, I know that Dyson ones lock

[@windshield11]

​@@mohamedelkady6237Makita locks as well

[@nelchan2421]

happy new year

[@djmulder]

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?

[@jBurn_]

I think it doe's not properly balance. It just shut's off if a too large inbalance is detected...

[@PhilippStadler]

Actually the cells weren't properly balanced in this video. What the external charger probably would do is bleed of some energy of full cells to bring them down to the lowest cell and then charge all up again to 4.20 Volt.

[@jcvjcvjcvjcv]

All poles are connected individually, so the charger can charger whatever cell(s) it wants.

[@kalisto1]

My Bosch battery wont charge, all cells are ok, fuse is ok. What could be wrong ? Doesn't charge when in charger.

[@josephking6515]

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. 👍😁

[@hectorguillen3511]

My 4Ah battery stopped working it denied the charge on a standard charger also in my 16 amp Bluetooth charger 3 days later after being 100% dead and couldn't even keep a bosch light on I decided to unscrew and pry the sides a little didn't even come apart maybe gunked up with dust and dirt I tighten the screw back on it started charging again 🤷‍♂️ okay I call that an easy win, however, it only goes to 4 bars instead of 5 bars furthermore my charger via blue tooth and the app says 100% charged strange fix

[@stevenbennett5451]

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?

[@montanacarvalo]

pero las celdas son de 3.7 volt

[@stevenbennett5451]

It’s actually reading 23v so looks like it’s overcharged?

[@jcvjcvjcvjcv]

@@stevenbennett5451 Where do you see 23V?

[@Shaun.Stephens]

@@stevenbennett5451 Is it an LG Cord Zero?

[@moresapa1147]

What would happen if after replacing start charging without balancing?

[@eW0LF]

You can do that. Balancing will be done with internal BMS.

[@NoName-sx4cz]

​@@eW0LFthats depends. If their is active balancing, yes although it will take some time. If its passive balancing only on the top end of the charge, it will take many many cycles to fully equalize the cells. Best to just balance while you have access to the cells.

[@donalexey]

@@NoName-sx4cz There is no active balancing, nor passive. The charger will stop charging at the 1st cell reaching its voltage limit. Others will remain undercharged.

[@NoName-sx4cz]

@@donalexey a lot of bms's, including the one I use on my lifepo4 battery, start balancing at a set voltage during charging, such as 3.2v. they balance while the cells charge, and yes cutoff once one cell reaches 3.65v with lifepo4. That is passive balancing. Active balancing will balance while not charging using capacitors to shift charge between cells.

[@donalexey]

@@NoName-sx4cz I was talking about internal battery charging controller of Bosch batteries. There is no BMS. I had to open the battery and change the cells on the table to make a failing Bosch battery charge again to its full potential. The original question was about not balancing the cell on the table before assembly.

[@nathanwest2304]

bosh seems to be kinda bad at making batteries out of 2 pro core and 3 bosh green batteries I had 1 dead pro core, one dead green and one defective green that has some contact issues with one of the sensor pins, also one of the bosch green batteries has no balancing at all, not even a PCB meanwhile I have 4 Wesco batteries, 2 genuine makita, 2 knockoff makita, 2 Facom(dewalt), 1 worx and 1 parkside battery that have all worked flawlessly for years

[@Z15TEENG]

You're Genious 😊

[@tevfikkeskin1834]

we watched how a quality work is done

[@aaronclark8877]

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

[@vegetablepolice1]

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

[@pileofstuff]

Most of the time it is only one or 2 cells in a pack that die prematurely rendering the entire pack "failed".

[@carloshnunez]

Good tip 🔵🔵🔵🙂🙂🙂👍👍👍🔵🔵🔵

[@dogukancil5128]

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.

[@jcvjcvjcvjcv]

There is no balancing on these packs. + and - are hardwired to the terminals (+ with a fuse).

[@CEzikMaj]

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

[@jimbarchuk]

Ridiculous.

[@gundogankazanc9241]

you're right properly. to measure the cells by a digital voltmeter, seems limited true, he should make it when the battery is loaded. with a big probability, other cells are damaged or died

[@gabbertje2811]

Yes and no. No 2 cells are the same even if they come from the same batch. Then there's temperature influence. Because of heat the middle cells have a harder life than the rest. Especially on the heavy used packs. It mostly depends on the way the BMS is designed if the pack is going to last after a partial cell replacement. Many tool brands don't have a balancing circuit in their batteries. Only cell monitoring so the cells tend to drift apart and the usable capacity gets less and less. Sometimes you can bring a dead pack back to life just by manually balancing it. Luckily more and more brands are implementing cell balancing. Fun fact: The first gen Bosch professional batteries (both 18V and 36V) didn't even have cell monitoring. Just a single thermistor for over temperature monitoring. Still wondering how bosch considered that safe because cells could easily go well above the safe 4.2V and general knowledge is > 4.2V = BOOM

[@reignreincarnation5531]

​@@gabbertje2811 had 2 of my molicel p26a went above 4.2v as i used old 18650 charger without digital display, just state of discharge for every 25%. Once completed i checked the battery with voltemeter and the volt of those 2 were above 4.3v, tried using the latest charger and it won't even able to recognize the battery as the volt way overcharged, luckily nothing happened as i leave them alone a couple of days for them to naturally discharge. A few days after i checked and their volt went down to 4.2++v and the latest charger able to recognize them and i put them into storage mode asap but their volt is higher then other batteries as they were discharged from higher volt. Since then i got myself a balance charger that can support 8s and on my way building 8s battery holder. if it's any unknown batteries it might've combusted or blown already, luckily those were molicel's.

[@vegetablepolice1]

use bench power supply man

[@jcvjcvjcvjcv]

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.

[@branimir2311]

Great, thanks !

[@viorsa8200]

Ok, fantástico trabajo.👍🤓😜

[@dlmm2645]

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.

[@aliancemd]

Bosch in a way is trying to do that, with AMPShare, but outside that program, all the manufacturers use their own proprietary communication protocol, so, the "no caveats" answer is "no". As you can see, with the exception of Bosch and Milwaukee, the manufacturers are also trying to introduce artificial market segmentation between "18V/40V", "20V/60V", because that makes more money, so there is really an interest for you to Not be able to use the same charger.