Konion cells in Makita are SAFER than many other 18650 !

Doctorbass

100 GW
Joined
Apr 8, 2007
Messages
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Location
Quebec, Canada East
want your ebike using powerfull 18650 without the fear of flammes and possible explosion?

2.1Ah and 12 miliohms! 30A

The Spinel LiMn chemistry of the 3 and 4 Ah are very safe! as you can see here:

Jump to 1:25
[youtube]sMWRyTHfgRA[/youtube]


Ok Ok.... not convinced yet?? and you think these was not charged?..

Ok let see how it does with 4.2v fully charged!!

[youtube]Bn5zhqz4LsE[/youtube]


Here are the specs o fthe VTC4 ( 2.1Ah cells) : https://www.powerstream.com/p/us18650vtc4.pdf



Doc
 
Doc, I know you know better than to spam the discussion forum with ads, where they are not allowed. :(

You should stick to posting them only in the for sale section where they are allowed.
 
amberwolf said:
Doc, I know you know better than to spam the discussion forum with ads, where they are not allowed. :(

You should stick to posting them only in the for sale section where they are allowed.

Amberwolf, it is now informative only. Post edited, Thank.

Doc
 
I have had many Makita cells 400 and just taking them apart carefully I have seen Flames shoot out the top of the cell. I bought as used defective packs returned to makita for Exchange. They could have had water damage or something else as they are used and defective and return to Makita. I've even seen makita packs with dented cells inside how would that happen I wouldn't know.
 
I have not read all the info out there on the web about the main causes of flaming lipos or 18650s or LiFePO etc. But from what I have seen the two causes that jump out at me is short circuits and over charging. But I may be wrong, wouldn't be the first time. I have seen many vids of nothing happening after punctures, crushing or cutting of Lithium cells of many different format. Let's see videos of the VTC4 cells being over charged.
 
Thanks for sharing your opinions and experiences with these and i encourage you guys, to continue.

Another great exemple is your own experiences with these Makita packs on E-S guys! mainly positive from what i have read and feedback i got. :)

But for sure if you make a search on that forum for people having makita cells based battery compare to all other cells type, did you ever heard one of these bursting in flames or exploding due to the cells themself?

Please make a search!.. and make the same search for lipo, Lico and all other 18650.

Fact are the best proof 8)

I had over 24 800 of these used packs in my garage in the last 9 years... yes 24 800! and out of them i rejected 71% . And never got any flames or explosion. Please could some of you guys do the experience with 24 800 lipo 10s packs or 1/4 million chineese 18650 over 9 years and sleep quiet every night :lol:

Please guys believe facts.. :wink:

Doc
 
Doctorbass said:
Thanks for sharing your opinions and experiences with these and i encourage you guys, to continue.

Another great exemple is your own experiences with these Makita packs on E-S guys! mainly positive from what i have read and feedback i got. :)

But for sure if you make a search on that forum for people having makita cells based battery compare to all other cells type, did you ever heard one of these bursting in flames or exploding due to the cells themself?

Please make a search!.. and make the same search for lipo, Lico and all other 18650.

Fact are the best proof 8)

I had over 24 800 of these used packs in my garage in the last 9 years... yes 24 800! and out of them i rejected 71% . And never got any flames or explosion. Please could some of you guys do the experience with 24 800 lipo 10s packs or 1/4 million chineese 18650 over 9 years and sleep quiet every night :lol:

Please guys believe facts.. :wink:

Doc

VTC4 are just awesome very robust 18650 cells.
I have not had any problem with any sparks of any kinds (YMMV I guess).
I'm really happy with the 25 Makita Packs (5S-2P 4Ah) I bought from DoctorBass ! Already tested 130 cells of the used packs. Of these only 2 were bad. The128 other were like new (I guess costumer ruterned them because of faulty BMS, with on average 104.6% of the rated Capacity !

See here : View attachment Makita VTC4 cells from doctorbass.xlsx
 
Thanks Matador!

This feedback is like many other comments i get about these great cells.

Doc
 
They are still very dangerous and may attack at any time. However, you should note that pressing lithium batteries won't usually make them flame up. They are being destroyed quickly, and in a way that does not allow them to build up gasses and heat. If you were to press a metal object such as a nut through the layers causing a short, but stop short of completely obliterating the battery cell - you would have more luck if you're trying to get a flame/explosion.
 
Kneelb4ZOD said:
?....... If you were to press a metal object such as a nut through the layers causing a short, but stop short of completely obliterating the battery cell - you would have more luck if you're trying to get a flame/explosion.
..Did you watch the video i posted above ? ( check at 2:45 in )
Exactly as you suggest, a nut pressed into a lipo pack...
One pack flares up.....but another pack just blows fumes ???
 
Kneelb4ZOD said:
They are still very dangerous and may attack at any time. However, you should note that pressing lithium batteries won't usually make them flame up. They are being destroyed quickly, and in a way that does not allow them to build up gasses and heat. If you were to press a metal object such as a nut through the layers causing a short, but stop short of completely obliterating the battery cell - you would have more luck if you're trying to get a flame/explosion.


Kneelb4ZOD, Welcome to the forum. Please, could you make a short description or presentation of you?.. well that's what people usually do and that E-S apprecaite :wink:

I dont know your background about battery but i would like to know why you assume that these are very dangerous? witch fact, test did you made or found to say that?
I just dont agree with you on that.
If the would be like you express, many powertool company could not use them in the battery they sell. Think about the very hard environment, impact, vibration, damage, very high and low temp these have to endure! You talk about these cells just like if they would be LiCo chemistry that we find in laptop that burst in flames.... witch i think never hapenned in any makita powertool or ebikes. I personally played and tested these over the lasy 9 years and know them very well. Maybe you give us your background and reference about lithium cells that could hlop us to understand.

btw on your other reply ( the 2nd on the forum) you said that the A123 26650 have the highest current rating witch is not.
A123 26650 (also known as M1 cells) are rated 30c continuous 60C burst for 10 seconds.. and today Lipo are way higher than that. some are even capable of 100C continuous and 200c burst. However A123 LiFepo4 are the best LiFePo4 i ever know and have the best cycle life and c rating on the industry. LifePo4 and Limn cells are very similar safety and power density, However they dont have the same discharge curve and voltage range.

Limn chemistry , just like the one in the makita are also used in the Nissan Leaf electric car.

Doc
 
Hillhater said:
These cell crush tests dont seem to prove anything conclusively.
If you watch these lipo packs being crushed, some flame up, others dont ???
https://endless-sphere.com/forums/viewtopic.php?f=14&t=86339


In fact it often depend on their state of charge!.. you can crush cells from all chemistry without getting any flames or explosion if they are at 0.0v

That's why the Sandia lab, a reference for battery testing, they, like many other test standard lab are specifying the SOC of the cells they test in destructive testing.

That's why you see sime lipo to burst inflames and some not.

That's also why we recommend to fully discharge lithium cells at low rate before to discard these... .. like a resistor in parallel.

Doc
 
IMHO,

Lipo pouch cells are much more dangerous than 18650....

I thing from most dangerous to least dangerous :

LEAST SAFE

1. Lithium-polymer pouche cells (insert chemistry type here --> ...... )

2. Lithium Cobalt Oxide (LiCoO2 or LCO) 18650 : really NOT made for eV : low drain only... will heat up a lot and might explode past certain temps.

3. Other commonly used 18650 for eBikes/eVehicles : LiMn2O4 or LMO (not best suited for eV), LiNiMnCoO2 or NMC (chemistry used in Nissan Leaf, this is what DoctorBass is selling), LiNiCoAlO2 or NCA (the chemistry used in Tesla ; NCA has a slightly higher energy density than NMC, but NMC can take higher amp drain).

4. LiFePO4 and Li4Ti5O12 are the safest of all... But they have horrible energy density and they have lower nominal voltage (3.2V for LiFePO4 and 2.4V for lithium titanate)

MOST SAFE

So the Makita cells seems pretty safe to me, just my two cents.

Reference used for this reflexion : http://batteryuniversity.com/learn/article/types_of_lithium_ion

Matador
 
What chemistry are the new westart 10ah graphene cells and how safe are they ? Li-Graphene ?
http://www.szwestart.com/. I'm having a hard time finding anything out.
It just sounds very fire safe ? Besides a short.
 
The new US18650VTC6 will be released soon, these are rated 3120mAh and can do 30 amp!... for me that is way better than any 3400mAh that can only do 7A and would probably explode at 30A before end of DOD !!

Their impedance is crazy low! about 8 miliohm !! just a bit higher than the famous powerfull 60C A123 26650 2.3Ah cells from 5-10 years ago

And for your pleasure guys... Makita will also offer a 6Ah pack soon! But not any sign in Canada about these yet...

The VTC6, like the VTC5 and VTC4 already have been reviewed on the popular Candlepowerforums website.

These are 10.5wh at 10A discharge!... or 95 cells per kWh got 10kW power!

VTC6 Official specifications:
•Typical capacity: 3120mAh
•Minimum capacity: 3000mAh
•Nominal voltage: 3.6V
•Standard charge: CC/CV, 0.2C, 4.2V
•Standard discharge: CC, 0.2C, 2.5V
•End-of-charge voltage: 4.2V +/-0.05V
•End-of-charge current: 0.02C (About 62mA)
•End-of-discharge voltage: 2.00V
•Continuous maximum discharge: 5C/10C (15A/30A) with temp cutoff at 80°C
•Max. discharge current vs. time: 30A-40A > 44s, 55A > 19s, 80A > 6s (Never discharge above 80°C)
•Cycle life: 300 cycles @ 0.5C to 80%
•Initial impedance: 8mOhm - 18mOhm ( lastest revision)
•Weight: 46.4g +/- 1.5g
•Operating temperature: Charging 0°C ~45°C, discharging: -20°C ~ 60°C
•Storage temperature: -5°C ~ 35°C


Sony%20US18650VTC6%203000mAh%20(Green)-Capacity.png



3rd party TEST result:
http://www.candlepowerforums.com/vb...st-Review-of-Sony-US18650VTC6-3000mAh-(Green)


Original SPECS: http://www.accushop.at/images/product_images/original_images/apdf/AccuShop_US18650VTC6.pdf


Doc
 
Very promising news about Makita 6Ah tool packs.

Doctorbass said:
The new US18650VTC6 will be released soon, these are rated 3120mAh and can do 30 amp!... for me that is way better than any 3400mAh that can only do 7A and would probably explode at 30A before end of DOD !!

I wonder which 3400mah cell you are referring to :roll:

And the added bonus will be that if the VTC6 cells find their way in Makita tool packs, you will gladly share an easy way how to take them apart. :lol: Now I'm just being nasty. :twisted:
 
mistercrash said:
Very promising news about Makita 6Ah tool packs.

Doctorbass said:
The new US18650VTC6 will be released soon, these are rated 3120mAh and can do 30 amp!... for me that is way better than any 3400mAh that can only do 7A and would probably explode at 30A before end of DOD !!

I wonder which 3400mah cell you are referring to :roll:

And the added bonus will be that if the VTC6 cells find their way in Makita tool packs, you will gladly share an easy way how to take them apart. :lol: Now I'm just being nasty. :twisted:

My guess would be the Panasonic NCR18650GA.... I also wonder how many mAh can be drawn out of them at 30 amps :lol: But please do not try this with GA cells.... they will explode for sure lol.
 
Doctorbass said:
I dont know your background about battery but i would like to know why you assume that these are very dangerous? witch fact, test did you made or found to say that?

"They are very dangerous and may attack at any time" is an inside joke for viewers of the Hydraulic Press Channel. After each episode, they have bonus content where they crush a clay animal. One of the catch phrases of the show which is said before squishing the clay figure is: "It is very dangerous and it may attack at any time, so vee must deal with it!" To clarify, I don't think the batteries are dangerous. That was a Hydraulic Press Channel joke. :lol:


Doctorbass said:
btw on your other reply ( the 2nd on the forum) you said that the A123 26650 have the highest current rating witch is not.
A123 26650 (also known as M1 cells) are rated 30c continuous 60C burst for 10 seconds.. and today Lipo are way higher than that. some are even capable of 100C continuous and 200c burst. However A123 LiFepo4 are the best LiFePo4 i ever know and have the best cycle life and c rating on the industry. LifePo4 and Limn cells are very similar safety and power density, However they dont have the same discharge curve and voltage range.

I agree with you completely. The topic was about 26650 cylindrical cells, and they are "just about the highest discharge rate you can find" in the category. I wasn't trying to say you can't find higher discharge Lipo batteries.

Doctorbass said:
Kneelb4ZOD, Welcome to the forum. Please, could you make a short description or presentation of you?.. well that's what people usually do and that E-S apprecaite :wink:

Is there a proper sub-forum to make an introduction? I don't want want to deviate too far off-topic, but I live in China and have worked in the electric vehicle industry. I also do work for a battery supplier, supplying primarily 18650 batteries in large quantities.
 
Here are some discharge curves
http://www.candlepowerforums.com/vb/showthread.php?205814-Lithium-18650-Safe-Chemistry-Performance-Shootout-5-10-15-Amps-AW-Added/page2
 
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