Samsung 25R/LG 18650HE2/ Sony VTC5 high power 18650 battery

[ecruz]

those little welders look really handy.

whats the general consensus on them, apart from the tips burning out, do they last ok?

The tips should last a long time and it comes with sets so I cannot see using all of them up with a pack. The only negative that I see on the spot welder is the thickness of the strip you can use. 0.01mm-0.12mm nickel or nickel belt connection with metal plate for parallel I imagine is fine but forget serial. But for the money I still think it is worth it. Hopefully I can make a video tonight for you guys.

 

[sflorlando]

any updates guys?

Excited to see how this turns out.

Ken

 

[ecruz]

Sorry! I tried this Sunday but mother in law came over LOL Anyone want to lend me some punctured lipos LOL. Tonight Im going to do it.

 

[arkmundi]

Hey thanks for the post and data sheets! Always interested in suppliers for legit good cells and building them into battery packs. FYI, Alibaba is the Amazon of the East. Actually it does twice the volume of Amazon and EBay combined! Ultimately, it is just a web store front for hundreds of thousands of companies based in China, Korea, Singapore, Malaysia and other high-tech countries. So just because its listed at Alibaba is not indicative of good or bad product. Look at the stats of the supplier you're being directed to. A good supplier will be protective of their reputation and not do nasty things like put counterfeit labels on cheap cells. I'd be interested in reporting on people's experience with various resellers of Samsung, LG and Konion cells.

 

[ecruz]

Ok guys got the video done. Hope it helps! Any questions feel free to ask.

http://youtu.be/3RfhTz_MP0A

 

[parabellum]

Ok guys got the video done. Hope it helps! Any questions feel free to ask.

http://youtu.be/3RfhTz_MP0A

Cool. Would love to see what it does with .2mm strip. Is the setting going up to 99?

 

[ecruz]

Ok guys got the video done. Hope it helps! Any questions feel free to ask.

http://youtu.be/3RfhTz_MP0A

Cool. Would love to see what it does with .2mm strip. Is the setting going up to 99?

Yes at 99 it welds for 5ms

 

[999zip999]

How much ? Plus what with the ghost smoke in the vid. hope it's not tobacco.
Found it 186.00 shipped.

 

[ecruz]

How much ? Plus what with the ghost smoke in the vid. hope it's not tobacco.
Found it 186.00 shipped.

Lol my girlfriend had incense in the coffee table where I was working on.

 

[Gab]

The 25R has been out for a few months now, and it seems the VTC5 also has been out for a month or 2 , so when will Samsung release the 25R replacement to beat the VTC5 as that's the best capacity cell now? Are battery released every 6 months it seems?

 

[sflorlando]

Thanks Ecruz

Exactly what I needed to see!

Ken

 

[ecruz]

I was watching a video on a large battery pack and saw something interesting. I was thinking of using the thickest possible parallel leads in the spot welding but how it should be done is use a lead that will melt just above the amperage that the battery can hold peak. So if a battery goes to blow it will burn the parallel lead before. So thought I share that with you guys as it makes sense it acts as a fuse from battery to battery. On the serial connections however you have to go thick to deal with the increased voltage and amperage.

 

[arkmundi]

Yes I tried to pull it apart and its not coming off. Its bonded well It will probably rip the spotweld clean with piece of battery. .... Here is a picture of the unit.

How much ? Plus what with the ghost smoke in the vid. hope it's not tobacco.
Found it 186.00 shipped.

FYI, that same spot welder can be found at Amazon for $168...
http://www.amazon.com/Hand-held-Welding-Machine-Laptop-Battery/dp/B00BWOUZDA/

This also available at Amazon for $72.48:
http://www.amazon.com/Pro-Grade-Ultra-Portable-100-Amp-Electric-Welder/dp/B000V663G8
... seems to be highly rated. Would be interested in opinion. Thanks.

 

[silentflight]

Thanks, ecruz! That was a fantastic video, just what I needed to consider buying a similar spot welder for pack building. I hope this video gets the number of views it deserves on the sphere. It is worthy of its own thread, otherwise some great resources just get buried in the heaps of posts over time.

 

[ecruz]

Yes I tried to pull it apart and its not coming off. Its bonded well It will probably rip the spotweld clean with piece of battery. .... Here is a picture of the unit.

How much ? Plus what with the ghost smoke in the vid. hope it's not tobacco.
Found it 186.00 shipped.

FYI, that same spot welder can be found at Amazon for $168...
http://www.amazon.com/Hand-held-Welding-Machine-Laptop-Battery/dp/B00BWOUZDA/

This also available at Amazon for $72.48:
http://www.amazon.com/Pro-Grade-Ultra-Portable-100-Amp-Electric-Welder/dp/B000V663G8
... seems to be highly rated. Would be interested in opinion. Thanks.

Just make sure you can use the 200v version I wanted to be able to use 110v as my 220v connector is only in the back of my dryer and there is no room for me there.

 

[tuurb]

Hi,

A question, to start talking back about the cells

I would like to make a 5S5P battery pack with or the VTC5 cells or the 25R cells.

If I do not want to balance charge regularly, should I go for the 25R or VTC5?
I would bulk charge about 50 times and then balance them once...

Please help,

Thanks,

 

[riba2233]

Doesn't matter, both of them have close production margins. If all cells are balanced well before use, they shouldn't get unbalanced. But you should monitor charging and you shouldn't discharge completely.

 

[arkmundi]

Hi,

A question, to start talking back about the cells

I would like to make a 5S5P battery pack with or the VTC5 cells or the 25R cells.

If I do not want to balance charge regularly, should I go for the 25R or VTC5?
I would bulk charge about 50 times and then balance them once...

Please help,

Thanks,

Doesn't matter, both of them have close production margins. If all cells are balanced well before use, they shouldn't get unbalanced. But you should monitor charging and you shouldn't discharge completely.

I'd agree, its my very approach with the A123 26650 12S8P cylindrical pack I just built. The cell damaging practice most likely to occur here among the ES DIY community is to over-charge, so if that is carefully regulated and monitored, the pack should stay relatively well balanced over time. Its when a cell is over-charged, sometimes over-discharged, that you'll change the internal chemistry and increase the internal resistance - IR - vital to maintaining pack health. Since mine is an expensive pack and I want it to last a long time, I first, don't over-charge. I'll bulk charge the pack to <80% SOC. Second, like you, I'll periodically tear the pack open and monitor the 12S strings AND the individual cells. I want to see voltage within a tolerance of 0.01 volts of each other - very well balanced in other words. If not, time to put the string on my the Thunder 1220 balance charger. If a cell is persistently off kilter, then I'll replace the one cell. Pack design helps a lot. So does having the right equipment.

 

[nukezero]

I bought Samsung 18650-25Rs, all 52 cells. See my other thread regarding the first home-built frame mounted battery pack. All cells were exactly at 3.64V when shipped to my house.

I am still using a BMS anyways. I have charged up the entire 48V pack to 54.1V before the charger shut off. After two days, the pack settled to 53.6V.

Overall, I would say these cells are darn good for the money. I would have wanted the Sony VTC5s though, but they are 40% more expensive.

 

[hillzofvalp]

One time I found data detailing the vtc4s internal fuse. I confirmed this through tests to 5V @5A.

Does the HE2 also have this feature?

Is the vtc series the only spinel (self balancing) series? If so, where is a good place to purchse 1000 cells? I noted a Skype contact in this thread but he didn't come up in the Skype contact search.

Anyone know how to get cells direct from Korea or Japan?

Thanks

 

[ecruz]

One time I found data detailing the vtc4s internal fuse. I confirmed this through tests to 5V @5A.

Does the HE2 also have this feature?

Is the vtc series the only spinel (self balancing) series? If so, where is a good place to purchse 1000 cells? I noted a Skype contact in this thread but he didn't come up in the Skype contact search.

Anyone know how to get cells direct from Korea or Japan?

Thanks

Guys there is a vendor in eBay called r-lsales tell him ecruz from es sent you he sells the vtc5 for $7 in large qty all his prices are good. I ordered and tested mine from him.

 

[silviasol]

This also available at Amazon for $72.48:
http://www.amazon.com/Pro-Grade-Ultra-Portable-100-Amp-Electric-Welder/dp/B000V663G8
... seems to be highly rated. Would be interested in opinion. Thanks.

Looking for a cheap solution to spot welding a pack. This would work but what would you use for the two elements?

 

[Ebikebert]

hey guys i just wanted to appologize for not finishing the pack yet i have been very busy with graduation for my highschool. I have tested a few cells @ 15A discharge before putting it together and they only got warm. These cells work really well from my initial tests.I am trying to finish the build now but i need some heatshrink to put around them. Does anyone here know where to get 160mm+ heatshrink thats not from china that will take weeks to arrive.

 

[dnmun]

Hi,

A question, to start talking back about the cells

I would like to make a 5S5P battery pack with or the VTC5 cells or the 25R cells.

If I do not want to balance charge regularly, should I go for the 25R or VTC5?
I would bulk charge about 50 times and then balance them once...

Please help,

Thanks,

Doesn't matter, both of them have close production margins. If all cells are balanced well before use, they shouldn't get unbalanced. But you should monitor charging and you shouldn't discharge completely.

I'd agree, its my very approach with the A123 26650 12S8P cylindrical pack I just built. The cell damaging practice most likely to occur here among the ES DIY community is to over-charge, so if that is carefully regulated and monitored, the pack should stay relatively well balanced over time. Its when a cell is over-charged, sometimes over-discharged, that you'll change the internal chemistry and increase the internal resistance - IR - vital to maintaining pack health. Since mine is an expensive pack and I want it to last a long time, I first, don't over-charge. I'll bulk charge the pack to <80% SOC. Second, like you, I'll periodically tear the pack open and monitor the 12S strings AND the individual cells. I want to see voltage within a tolerance of 0.01 volts of each other - very well balanced in other words. If not, time to put the string on my the Thunder 1220 balance charger. If a cell is persistently off kilter, then I'll replace the one cell. Pack design helps a lot. So does having the right equipment.

is there a thread somewhere that documents that the cell chemistry is damaged if it is charged to full voltage?

how does a charged resting voltage indicate what the capacity of the cell is?

i am under the impression that the cell voltages when the pack is discharged have to be very close to each other at full discharge in order to say that the cells are balanced to each other. not at full charge.

balance indicates that the cells each store an equal amount of charge so the voltages at the end of the discharge are close or equal when the pack is discharged. that indicates that the capacity is equal, or "balanced".

 

[ecruz]

Ok guys got the video done. Hope it helps! Any questions feel free to ask.

http://youtu.be/3RfhTz_MP0A

Cool. Would love to see what it does with .2mm strip. Is the setting going up to 99?

Received the .2 strip and tested it. First I put the current to 45 vs 35 worked perfectly. Then went up to 55 and it welded a slightly bigger dot. When I did a second one at 55 my breaker tripped lol. Granted I did it in the living room on a 15amp breaker. 20amp breaker recommended minimum for 55.