This Should be Illegal… Battery Repair Blocking

[BroktonHarris]

I have a few tips for you on rebuilding batteries. The first is if you rebuild a battery like a laptop battery for example then you will actually need to send a small ''jolt'' of energy into the bms thru the bms for a 2s or 7.4 v battery this involves simply inputting 7.4 v on the respective positive and negative terminals. If you also want to have a better weld quality than a pair of tungsten welding tips would be a good investment. As for the tabs coming off you actually need to turn your current down by about 25% and do three weld spots instead of 2 

[Luscious]

If the cameras have a DC barrel input then the solution is pretty obvious - just go make a proprietary pack yourself. You can get 18650 holders easy and if you have other sizes like 26800 and 32700 3D print your own or have a shop do it.

 

One easy fix for external DC input for devices like cameras is also to get a 12V DC car adapter. That's especially handy for devices that may not have a battery power source but let you run a 12V DC car lead for power. At that point you don't even need to make your own pack since many places will sell you a finished 12V battery complete with charger and 12V car receptacle. And since these are 3rd party batteries the seller/supplier can most likely service it. Another option is to get a battery pack and pair it with a DC-to-AC inverter - efficiency not so good but your AC device will gain portability!

 

Bixpower.com is a great source for batteries like this. They are local to me and I have purchased from them in the past, including an external 98WH battery for my Surface tablet with the special Microsoft connector that you just cannot get ANYWHERE. I also have a pair of their monster BP220 packs with the parallel Y connector - used with my XPS 13 I have run this laptop for over 24 hours without going near an AC outlet.

 

I would have recommended BatteryBlocs as well except they are no more - Shawn was a pioneer in the DIY battery space and put much work and design into his product.

 

This video is an excellent guide on how to work with 18650's and spot welding - Tony is a true master, and if you followed his ebike story from a few years back you will know he does a bulletproof job with this stuff.

 

Now if you really want to kick things up to the big league go check out Aims Power - they will do batteries, DC to AC, solar and off-grid systems for anything from as small as a utility cart all the way to a commercial building. They are particularly good at solar trailers - basically a flat bed towable with solar panels that fold out either side and have massive battery banks and pure sine inverters that can push thousands of watts with even generator backup for 24/7 power if necessary. Handy for EV charging in the middle of nowhere, bikes/scooters but also temporary power for building sites, large events etc... Make it a permanent install and you would have enough juice to power a modest server rack in case of a major power outage.

[Charun]

Sure this probably already been said, but when you sand your terminals down you're gonna leave a bit of sanded metal dust on the tips and you're dealing with a lot of current and you're basically melting those tiny "metal" pieces to boiling point hence the sparks its oxidizing very rapidly , those are not shorts, you need to clean your rips with a cloth to rid the tips of small bits of dust of metal OR just get better spot welding tips, pure copper only. Stop being a bunch of scaredy cats you just created a lot of more fire hazard when you dispose of good cells like that, probably in the bin. as much you like to think you're making a video for the goodwill...I tried to be less mean but seriously...

[rushboarduk]

I would hope companies like RED are rigorous in testing the batteries prior to sale, even if they add hardware fail-safes to prevent DIY replacement.

 

The legal system would probably have a lot to say about whether planned obsolescence, or cutting corners to make the cost of manufacturing less expensive, is illegal. However, in terms of prosecution, I suspect they would more likely pursue companies guilty of the latter than the former...

 

I absolutely would be interested in a visit to the Retriev offices.

[mariushm]

Way too paranoid about the spot welder and sparks on the batteries as others have said. The batteries are most like fine.

 

Proper way would have been to use an adjustable power supply set at the voltage of the batteries and limited to something like 50-100mA , connect the power supply to the BMS terminals so it doesn't detect the string of batteries as disconnected, build the new battery pack and connect it to the bms, then disconnect external power supply.

The catch is you have to be super careful about the soldering iron used to attach the power supply to the bms or to use a heat gun and paste solder to attach leads - some soldering iron tips are not esd safe, not grounded, so you could fry the bms chips with voltage from the soldering iron.

Some BMSes are extra naughty and also monitor balance wires, so the proper voltages would also have to be made available on those wires.

 

The chips on the BMS can also monitor and log the actual charge capacity so the charge IC may stop charging the new batteries prematurely once it measured that much charge got into the cells... yeah, it sucks.

[riba2233]

Well, as someone who made battery powered welders semi-professionally (JP spot welder, one that is being copied now by lot of folks), I can tell you that spot welder you used in the video sucked balls big time. 

 

You can see it by the naked eye, it lacks welding current and has too long pulse so it just melts the material, and it can go through the cell which is very dangerous. You need something in range of 1500-2500A for 5-10ms for a nice, high quality weld. And without that you shouldn't even try to do this.

Also, the welding electrodes you used were also very bad, to thin and dull and they get eaten away really quickly.

[SoCalBryan]

22 hours ago, HenrySalayne said:

Why do these cells even have to be welded together? There could be spring-loaded contacts on the underside of the BMS PCB and another PCB on the other side and the entire thing is just a 18650 sandwich and held together by the housing. Recycling and re-celling would be much easier.

The springs would melt or would deform due to the currnent passing through such a small wire.

 

[riba2233]

27 minutes ago, SoCalBryan said:

The springs would melt or would deform due to the currnent passing through such a small wire.

 

There are ways around this:

 

https://endless-sphere.com/forums/viewtopic.php?f=31&t=88051

 

Also VRUZEND kit which is not that good but works for some applications.

[Kilrah]

It's used to power professional equipment, you don't really want your shoot to depend on none of your 32 contacts deciding to be scratchy on that particular day...

Yes there are parallel cells, but it's one thing to worry about that nobody wants.

[spartaman64]

On 2/13/2022 at 1:22 PM, Ubersonic said:

Gotta be honest, this is one of the very few situations where I actually agree with the manufacturers locking things down. Considering the amount of laptops I've seen damaged by chinesium grade replacement batteries I think a company selling and warrantying $6000 cameras should be allowed to stop customers from using non-OEM batteries.

 

We have a rule in work against using reconditioned battery packs or packs from non-major brands purely because the fire risk however small simply isn't worth the cost saving.

except the original batteries are probably also chinesium batteries. you can buy a "third party" battery for iphones that are made by the actual manufacturer for iphone batteries in china

[BroktonHarris]

On 2/13/2022 at 11:08 AM, HenrySalayne said:

Why do these cells even have to be welded together? There could be spring-loaded contacts on the underside of the BMS PCB and another PCB on the other side and the entire thing is just a 18650 sandwich and held together by the housing. Recycling and re-celling would be much easier.

the only major use of this is to charge large quantity's of battery's at the same time

[scootcoupe]

So I thought this was an interesting video and is actually right up my alley with stuff I do as a hobby. The spot welder they are using is archaic by any measure and is almost guaranteed to give a failed weld eventually even at the hands of a professional. There are some dual pulse welders out there based on arduinos and a couple of mosfets that give a short duration pulse to clean the oxides off of the metal in preparation for the main weld and then give a much larger pulse to actually fuse the working material together. This is still an older technology for welding but works okay.

 

The best weld technology currently available to the hobbyist is actually measuring the energy input into the weld. https://www.keenlab.de/index.php/product-category/kspot-welder-kit/ is the welder that I currently use and is in my mind the best there is. You dial the energy in millijoules that you want to put into the weld and then it turns the output transistors on for however long it takes for that amount of energy to go in the welding leads. It runs off of a group 24 or 31 car battery, automatically compensates for variations in input voltage and also compensates for irregularities in the nickel strip/cell contact. The guys over at the endless sphere forum have pretty much standardized on it for building e-bike batteries. 

 

Also, you have to use a decent car battery, the welder puts out some serious current, on the order of 1200 amps, so much so that you actually feel the lead wires jump from the magnetic field generated by the flowing current. 

 

Also, I'm surprised with all of the prusa printers that they have that the LTT crew didn't just print a cell holding jig for their red battery. Takes no more than 15 minutes in solidworks and you are guaranteed a much more professional result.

[Just that Mario]

On 2/14/2022 at 12:10 AM, Egg-Roll said:

In this video he basically said removable phone batteries can't handle the future and are bulky which both are lies, sealing up phones are just simply cheaper and better for their bottom line in both manufacturing cost and obsolescence.

 

Linus can't bring up a issue for one product and ignore the biggest issue out there that is far worst of an issue than camera batteries.

So I have a question for LTT, when are you going to start talking about the non-(self)repairable status of our cell phones? You know the units we all own at least one of? The units that get thrown away possibly improperly (actually likely in many places) in the millions per year?

Not sure if bait...

[Just that Mario]

18 hours ago, spartaman64 said:

except the original batteries are probably also chinesium batteries. you can buy a "third party" battery for iphones that are made by the actual manufacturer for iphone batteries in china

While it is true, often these "OEM" ones didn't fully meet the specificiations but work "well enough". Personally I think battery replacement/"rebuilding" DIY shouldn't be something that every person has access to. I've seen some "yeah, don't f*cking do that" kind of questions on this very forum. I cannot even think what kind of a bomb they'd build if they had more access and encouragement from OEs.

[riba2233]

On 2/15/2022 at 12:34 AM, scootcoupe said:

So I thought this was an interesting video and is actually right up my alley with stuff I do as a hobby. The spot welder they are using is archaic by any measure and is almost guaranteed to give a failed weld eventually even at the hands of a professional. There are some dual pulse welders out there based on arduinos and a couple of mosfets that give a short duration pulse to clean the oxides off of the metal in preparation for the main weld and then give a much larger pulse to actually fuse the working material together. This is still an older technology for welding but works okay.

 

The best weld technology currently available to the hobbyist is actually measuring the energy input into the weld. https://www.keenlab.de/index.php/product-category/kspot-welder-kit/ is the welder that I currently use and is in my mind the best there is. You dial the energy in millijoules that you want to put into the weld and then it turns the output transistors on for however long it takes for that amount of energy to go in the welding leads. It runs off of a group 24 or 31 car battery, automatically compensates for variations in input voltage and also compensates for irregularities in the nickel strip/cell contact. The guys over at the endless sphere forum have pretty much standardized on it for building e-bike batteries. 

 

Also, you have to use a decent car battery, the welder puts out some serious current, on the order of 1200 amps, so much so that you actually feel the lead wires jump from the magnetic field generated by the flowing current. 

 

Also, I'm surprised with all of the prusa printers that they have that the LTT crew didn't just print a cell holding jig for their red battery. Takes no more than 15 minutes in solidworks and you are guaranteed a much more professional result.

 

Oh yeah kspot is probably the best copy of my welder A bit expensive if you only make a pack or two, but it has a lot of neat features. Downside is that those features make it less reliable. But I like to see the progress in this field, battery repair is imho very important but also potentially very dangerous as there are not many resources and it can go very wrong if you make a mistake. I wanted to make this job more accessible with welder that makes much better welds than chinese transformer based welders that were sold back then (2014-2015). 

 

If anyone is interested or wants to know more, here are some resources:

 

https://endless-sphere.com/forums/viewtopic.php?f=14&t=68005

 

 

And my old spot welder that I open sourced since I stopped selling it:

 

https://endless-sphere.com/forums/viewtopic.php?f=14&t=102681

 

It as all the drawings you need (even for electrodes), it is dual pulse and it only requires 12v car battery in 45-110ah range and regular barrel plug 12vdc adapter.

[Guest]

@Linus - I miss the good old days where you could pop a bunch of Duracell D-Cell batteries into a portable tape deck. Remember those 80s/90s Boombox Portable Stereos with Double Cassette Deck and Detachable Speakers?

 

I wonder... Is it possible to power a laptop using only (non- lithium) Duracell D-Cell, or even PC908 / 4R25 Block Batteries?

[AdmiralKird]

11 hours ago, Shawn Hopscotch said:

@Linus - I miss the good old days where you could pop a bunch of Duracell D-Cell batteries into a portable tape deck. Remember those 80s/90s Boombox Portable Stereos with Double Cassette Deck and Detachable Speakers?

 

I wonder... Is it possible to power a laptop using only (non- lithium) Duracell D-Cell, or even PC908 / 4R25 Block Batteries?

Well you've got two approaches, the first is through the DC port. A D cell is 1.5v, most laptops are 19v so you'd need 12 in series. The second is to go through the battery port internally which are usually around 3v or so, so you could possibly get by with 2, 3 but there are going to be battery communication issues since you'd lack the bms. Also depending on the laptop manufacturer, if you don't have a special chip in there, looking at you Dell, its gonna run like a dog under anything that isn't told it can draw at full speed.

[Science-Raven]

I designed a lithium boxing technology that can last 50 years and has higher power copper contacts than normal nickel welding can process... I can offer LTT a piece % of the startup company if he can help me tell engineers about the technology.

 

[Zodiark1593]

On 2/16/2022 at 1:53 PM, Shawn Hopscotch said:

@Linus - I miss the good old days where you could pop a bunch of Duracell D-Cell batteries into a portable tape deck. Remember those 80s/90s Boombox Portable Stereos with Double Cassette Deck and Detachable Speakers?

 

I wonder... Is it possible to power a laptop using only (non- lithium) Duracell D-Cell, or even PC908 / 4R25 Block Batteries?

The problem with Alkaline cells is their internal resistance. You can certainly get enough voltage from D cells in series, but you lose a lot of capacity when you start pulling a lot of current from them. A D cell isn’t going to do great under a 3 amp load. 
 

Given the power draw of mid-high end laptop chips, you’d probably want a 6S 3P configuration for a total of 18 cells. This gets you a working voltage of over 7.2v (a match for common 2S Li-Po battery packs in thin and lights), and should have the load spread enough to mitigate the effects of internal resistance. Don’t think it needs to be said why this isn’t the most workable of ideas for a laptop though. 

[MuhammadTaimoor]

Hello linus/ Linus team whoever and whenever read this comment (if they do) I literally just fresh signed up to this forum just so i could reply and tell you a genius way to fix whatever batteries you couldn't fix because of whatever the reasons.

 

I Watched the video thoroughly, you stated all the good facts about BMS and how you think in this case of red magic battery or the small packs with similar BMS, if they had to do something with either smart of evil BMS. 

I am writing this because you pretty much fried the BMS yourself. In my opinion RED wasn't trying it make it like you can't swap the batteries, they must have really thought of the integrity though and why no one should try to open it up and just so nothing hazardous happens like fire/short circuits anything. We all know the manufacturers make them so that nobody can open them up and you know mess with it, if it dies they can just say well you shouldn't have just messed up with it in a first place and they're not wrong? if it was catastrophic not all the victims would take the blame for it.

Now about the actual repair/swap of individual batteries. Ok so if the battery back doesn't have an physical EVIL SWITCH inside its case which usually releases in some electronics as soon as you pry them open and just completely resets and suicide on its own because of hardwired code in one of its chip, I believe everything is repairable, even evil ones can be repaired if you can figure out where that actual physical button is which gets released immediately upon opening. But i am here to talk about the Battery Packs. So far i haven't been able to get my hands on one of the EVIL BMS battery packs with an actual physical suicide switch inside them. I have opened tons of battery packs and repaired almost all of them with at least 95% success rate xD

So about the battery packs you showed in the video, I'll be specific to those only, well the ones you had your hands on from RED, No matter why they died, due to poor soldering or not having the same voltages in all cells, or even if the BMS could sense the disconnection of individual cell from a module and fry itself, could be anything. Most likely it was a self-suicide of BMS because of disconnection of the cells.

 

I have a way you can bypass all the issues with just 1 simple trick  I hope it works for you because i am a little tech freak and it hurts my bones to see so many battery packs going to waste when oh well, they all can be repaired by just cells swapping in your warehouse. 

The trick is to Measure the total output of BMS dividing it by total number of individual cells connected to BMS directly. The reason i said total number of individual cells connected directly with wires to the BMS is because In some cases like if your BMS is giving output of 16 v for an example, its most likely its a 4S BMS which means typically it should have 4 cells in series attached to the BMS but the pack itself could have 8 or 12 or 16 batteries ( in this case, 2, 3 ,4 packs of 4 Cells in series must have attached in parallel) to Increase the Capacity but maintaining the same voltage. So Make sure you know how many wires from the batteries are connected to the BMS you can just Minus 1 (number of wires connected from batteries directly minus 1) That'd be S (number of cells) for your BMS. 

 

You dont need to worry about each cell capacity if you take a reading of individual cells that'd be a plus point, Why? Because in Idle state just like you mentioned in video some BMS could actually keep a record of charged capacity, but in this case its totally invalid since battery isn't connected to anything. In idle state the Smart BMS only knows how much it charged or how much it has discharged from the start charge. So obviously you're doing this swapping repair in an idle state meaning its not powering anything which is a normal thing to do so you don’t have to worry about if it will detect there's a change in capacity (IT CAN'T DO THAT IN IDLE STATE) 

Once you have measured the Total output of BMS, Figured out how many wires are soldered or spot welded directly from batteries to the BMS And maybe count the individual Cells voltage, NOW The FUN TIME STARTS. there are 2 ways to do this. One is easier and quicker (works 100 percent of the times) and second one is lengthier and takes more time but it gives you satisfaction that you successfully not just repaired your pack but its better than the new one.

 

What you got to do is, you need to FAKE input voltage to individual cells. Lemme explain how. So basically, 95 percent of batteries BMS die because of Cell detection feature so they know when any individual cell loses its power or it’s taken out or tried to swapped, in all the cases it'd just suicide itself.

 

You need Small Power supplies. If your battery pack is 4S. you need 4 supplies set at 3.90-4.1 volts. I wouldn't recommend setting supplies to 3.7 (its considered almost discharged and most of the advanced BMS don't let batteries drain to that voltage) neither above 4.2 ( frequent used batteries and advanced BMS either stops charging or use the onboard resistors to drain extra charge if they sense it) 

You need to fake input these supplies voltages directly to the BMS on the solder points where all the batteries are connected, it’s going to be tricky, you'll have use jumper wires in some packs you'll have to think outside the box but the trick is same, you just fake input the voltages to individual cell on BMS directly, once you do that well you can happily just cut off/take off all the batteries right away and place a new mod battery module and solder it or spot welt to the BMS just like it was before.  

2nd method is same you must apply fake voltages so that the BMS thinks there's nothing to worry about and no one is trying to temper with it, this method actually needs you to measure the Individual Pack voltage and set your external voltage supplies accordingly. For instance, if it’s a 6S Battery pack of 22-24v ( could consist just 6 cells or 12 or 18 blah blah, dont care about it) just measure those 7 wires on BMS, they all should be like ( 1S "4.24v, 2S "4.12v, 3S "3.99v, 4S" 4.04, 5s "4.01", 6S "3.8" ) Whatever readings you get from the individual wires attached to the BMS, note them and set your Power Supplies accordingly with the same voltages and Just fake input them (like you're just giving it the same voltage it already has xD) And i give you my word with the kind of gear you have laying around in your warehouse I believe you'd just not have 95% success rate but a 100% I am ngl. 

 

I hope it works out for you, I hope you could revive if not all, most of your battery packs  I hope it helps you. I am not very good at explaining, i just tried to break it into little steps so maybe it all makes sense. But it works like a charm  you'll know if you read this comment and give it a try some day
Have a Good Day Linus/Linus Team.

 

[Just that Mario]

On 2/13/2022 at 10:28 PM, Zodiark1593 said:

Disagree. The manufacturer needn't facilitate it, but they also needn't take measures explicitly to prevent cell replacement altogether. If a customer is determined to go this route and have the skill to carry it out, manufacturers should stay out of the way.

Then the user also should take all the responsibility. But we all know they'd most likely try to blame it on the manufacturer.