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

[ridethelightning]

found this cool testing list from our friends the vapers :lol:
https://www.e-cigarette-forum.com/forum/blogs/mooch.256958/

 

[spinningmagnets]

This is useful info because...a typical E-biker will accelerate from a stop, drawing max amps. And then...during the cruise phase, the motor/controller/and battery pack can cool down when using a lower continuous amp-draw.

When a vape-enthusiast has adjusted a vaporizer to use high amps, they use high amps on every draw. (they call it low resistance vaping, due to the low resistance of the heater wire that is used for that).

If they have verified the Samsung 30Q as a 15A continuous cell, a tiny 5P pack provides 75A continuous (100A peak?). I don't know about the rest of the cells listed.

 

[Green Machine]

the vapor guys dont know their batteries at all.

That chart looks like it was made based on what the 18650 makers claim as their amp rating.

I have been spending a lot of time tryng to convince the vape community that rebranded cells such as efest and mxjo are junk....

currenlty the mxjo is the most popular batteries in the vape world. Mostly becuse mxjo will claim ridiculous numbers like 30-35 amps.


The mxjo has been proven to be a grade b LG HE4 rewrapped.

The fake sony Vtc5s that plaque the vape world are mostly rerapped samsung 25rs

 

[ridethelightning]

the vapor guys dont know their batteries at all.

That chart looks like it was made based on what the 18650 makers claim as their amp rating.

I have been spending a lot of time tryng to convince the vape community that rebranded cells such as efest and mxjo are junk....

currenlty the mxjo is the most popular batteries in the vape world. Mostly becuse mxjo will claim ridiculous numbers like 30-35 amps.


The mxjo has been proven to be a grade b LG HE4 rewrapped.

The fake sony Vtc5s that plaque the vape world are mostly rerapped samsung 25rs

Sorry but i beg to differ.
I would not have bothered to post the table if it was just based on the manufacturers specs.
if you read the couple pages of blog before the tables in the link, the guy actually tests the cells himself. the different colours in the table relate to the temps reached at a given CDR
he is, i believe, foremost a battery enthusiast before a vape enthusiast

he also discusses re-wrapped cells, and why NOT to trust the manufaturers specs.

I think the vapers are doing us a great service, because they are often using single cells and stressing the crap out of them, every day, untill they give out.
this gives us great insight about what different cells are really capable of, particularly the high discharge ones they also like.
they are going to know what the compared expected cycle life of different cells is when hammered, way before someone with a large ebike pack will.

 

[Punx0r]

Cool. Sounds like one vaper who does know their 18650s

 

[Green Machine]

Sorry but i beg to differ.
I would not have bothered to post the table if it was just based on the manufacturers specs.
if you read the couple pages of blog before the tables in the link, the guy actually tests the cells himself. the different colours in the table relate to the temps reached at a given CDR
he is, i believe, foremost a battery enthusiast before a vape enthusiast

he also discusses re-wrapped cells, and why NOT to trust the manufaturers specs.

I think the vapers are doing us a great service, because they are often using single cells and stressing the crap out of them, every day, untill they give out.
this gives us great insight about what different cells are really capable of, particularly the high discharge ones they also like.
they are going tp know what the compared expected cycle life of different cells is when hammered, way before someone with a large ebike pack will

I stand corrected that is an amazing blog post..i just saw the table and assumed it might be based on just claimed amp rating. I did not know someone in the vape world actually temp tested cells etc...this guy did an amazing job and is doing a great service to the vape world which needs more of this type of thing.

I am a vapor too and am co owner of wakeandvape.com with my girl friend. We published several big blog posts about vaping and 18650s including this buyers guide: http://www.wakeandvape.com/blog/18650-battery-buying-guide-for-vapor-users/

As a crowd the vape scene really needs more info written on which cells are worth buying. Because I am and know other big vape distributors i know for a fact that the MXJO is the most popular battery in the vape world right now....and it is a re wrapped LG He4 wholesaling for twice the price.

That wave is changing right now....and the most popular battery is becoming the LG HG2. I like to see that wave because atleast the HG2 is a name brand battery with some respect behind it (LG)

 

[madin88]

That wave is changing right now....and the most popular battery is becoming the LG HG2. I like to see that wave because atleast the HG2 is a name brand battery with some respect behind it (LG)

A big battery supplier told me that Samsung 30Q likely is the better choice, because LG HG2 and also HE2 / HE4 do wear faster and have more drift than similar Samsung cells.

 

[BatteryMooch]

Indeed each samsung INR18650 25R is capable of ~35A amps continuously, but in this case the voltage drops ~0.9V respect 1A discharge.

I'm the one who created the 18650 Battery Safety Grades table posted by ridethelightning. In my testing (which forms the basis for that safety table) the 25R rose to almost 100°C when discharged at 25A down to 2.8V. Both the 25R2 (blue) and the newer 25R5 (green) did this. At 35A both of them would be great danger of venting. The separator itself starts to melt at 120°C-130°C and the inside temp of a cell is always a lot hotter than the outside.

Based on cell temperature and lack of apparent cell damage during multiple 20A discharges I gave the 25R a CDR of 20A and recommend not discharging it at much above that. That 97°C temp it hit in testing at 25A was for a single cell in open air. In a sealed pack, with other hot cells, the temperature would be significantly higher.

 

[BatteryMooch]

This is useful info because...a typical E-biker will accelerate from a stop, drawing max amps. And then...during the cruise phase, the motor/controller/and battery pack can cool down when using a lower continuous amp-draw.

When a vape-enthusiast has adjusted a vaporizer to use high amps, they use high amps on every draw. (they call it low resistance vaping, due to the low resistance of the heater wire that is used for that).

If they have verified the Samsung 30Q as a 15A continuous cell, a tiny 5P pack provides 75A continuous (100A peak?)

In my tests, the 30Q actually tests out to a darn good 20A cell...a classic Samsung underrating of the cell. It's essentially identical to the LG HG2. At 20A both the 30Q and HG2 delivered about 15% more capacity than the 25R at 20A down to 3.2V.

 

[BatteryMooch]

found this cool testing list from our friends the vapers :lol:
https://www.e-cigarette-forum.com/forum/blogs/mooch.256958/

Thanks for posting that table! It's a summary of my cell testing to date and is updated at least twice a week with new cells as I finish testing. The table helps vapers select a cell and discharge current value that should be safe to use. A little more detailed explanation of the table and how the cells are "graded" can be found here:

https://www.e-cigarette-forum.com/forum/blog-entry/18650-safety-grades-picking-a-safe-battery-to-vape-with.7447/#comment-13213

A complete list of the cells I have tested, amd links to the test results, can be found here:

https://www.e-cigarette-forum.com/forum/blog-entry/list-of-battery-tests.7436/

I feel very strongly that temperature is a very important part of any cell testing and it's been very frustrating to see so many cell testers/reviewers not taking temp into account. How can anyone determine if a cell is ok to use if you don't know how hot it gets? And what about cycle life? It might not vent at 100°C but it sure as heck won't last very long running at that temp!

OK, rant over.

 

[docnjoj]

Hey Camlight. I'm not a smoker but I do respect your engineering background. Thanks for this info.
otherDoc

 

[ridethelightning]

thanks for owning up to that awesome table Camlight! :lol:

I feel very strongly that temperature is a very important part of any cell testing and it's been very frustrating to see so many cell testers/reviewers not taking temp into account. How can anyone determine if a cell is ok to use if you don't know how hot it gets? And what about cycle life? It might not vent at 100°C but it sure as heck won't last very long running at that temp!

OK, rant over.

this is exactly why i was excited to find the info you worked hard to produce.
hardly anywhere will you find info on temp vs discharge current for cells..its nearly always about capacity, current and voltage blah blah.
you generally have to make an educated guesse based on the cells' IR from the specs, what sort of temps its going to get to.

I also think temperature is a major factor to take into account. even if your pack gets to say 40-50C, the electrolyte will not like it . let alone 80-100C


when you spend 1.5-2k on a pack, its got to be a major consideration.

 

[ridethelightning]

btw. from your experiences, how do the 25r and 30Q compare when it comes to 20A discharge. do the 30Q get much hotter?

these are the 2 cells i am most interested at the moment.

particularly weather the 30Q are actually going to hold up well cycle life wise if you ask for 20A peak from time to time.

will the 25R maintain their capacity better than the 30Q over time if used in this way??

 

[Punx0r]

The Sony VTC5 seems to just edge out the Samsung 25R, but it's literally twice the price and fakes abound. A friend reported the 30Q didn't perform as well as the 25R in his sub-ohm (0.3 or 0.4 ohm from memory) vape.

It's about time someone produced a milli-ohm mod powered by A-spec nanotech

 

[bellfador]

Many thanks CamLight for battery test work and sharing data.

Yes, temperature is the key for the hidden questions. Recently I made a few tests on panasonic/sanyo 18650GA and ration between DC internal resistance, current and temp (Kelvin losses). First I put battery in termally isolated environment, heating with 1W (1 J/s) and calculate 55 J/*C thermal capacity. This mean when losses is 1W battery temp will rise each second with 0.0181 *C. After that I discharge battery with 5A expecting 1W loss (40 mOhm DC internal resistance). But battery heat up 0.025 *C/s or 40 J/*C. I repeated several times all tests and differences were max 5%. Accuracy for my measurement devices is 1%. Efficiency of chemistry changes added more losses and DC internal resistance not determined correct current heating. Have more tests to do...

Defense video for effest 35A 2800mAh (maybe LG HG2 ): https://www.youtube.com/watch?v=dYM80n88Zew
From this test I calculate average 48-55 J/*C but chemistry, environment and current are different.

The Sony VTC5 seems to just edge out the Samsung 25R, but it's literally twice the price and fakes abound. A friend reported the 30Q didn't perform as well as the 25R in his sub-ohm (0.3 or 0.4 ohm from memory) vape.

It's about time someone produced a milli-ohm mod powered by A-spec nanotech

LiPo is not save. If LiPo is in 18650 shell capacity will be near 1Ah... close to LG HB6.
Internal resistance is in close ratio with specific capacity ( mAh/sm^2). Hire is my idealized chart for the best 18650 cells:

 

[BatteryMooch]

btw. from your experiences, how do the 25r and 30Q compare when it comes to 20A discharge. do the 30Q get much hotter?

these are the 2 cells i am most interested at the moment.

particularly weather the 30Q are actually going to hold up well cycle life wise if you ask for 20A peak from time to time.

will the 25R maintain their capacity better than the 30Q over time if used in this way??

You can check the 30Q and 25R tests I did for the exact number but I think the 30Q runs about 6°C hotter at 20A (continuous) than the 25R. But, the LG's all run hotter than the Samsungs if I remember correctly. Six discharges at 20A for the 30Q showed no capacity fade or additional voltage drop, if that helps at all. For me, that's a good sign that you'll get decent cycle life at 20A, expecially when non-continuous discharges are done.

 

[BatteryMooch]

Hey Camlight. I'm not a smoker but I do respect your engineering background. Thanks for this info.
otherDoc

Thanks!
I only smoked occasionally, when quite stressed out, but since I started vaping I haven't lit up once! And this is using 0% nicotine liquids! I think for me the physical process of smoking was a big part of it. Just being able to stop, head outside, and smoke I guess was a powerful draw for me. Vaping has replaced that now.

And, the gear is shiny!

 

[ridethelightning]

I smoked a looong time ago...but never exhaled :lol:

 

[BatteryMooch]

Many thanks CamLight for battery test work and sharing data.

Yes, temperature is the key for the hidden questions. Recently I made a few tests on panasonic/sanyo 18650GA and ration between DC internal resistance, current and temp (Kelvin losses). First I put battery in termally isolated environment, heating with 1W (1 J/s) and calculate 55 J/*C thermal capacity. This mean when losses is 1W battery temp will rise each second with 0.0181 *C. After that I discharge battery with 5A expecting 1W loss (40 mOhm DC internal resistance). But battery heat up 0.025 *C/s or 40 J/*C. I repeated several times all tests and differences were max 5%. Accuracy for my measurement devices is 1%. Efficiency of chemistry changes added more losses and DC internal resistance not determined correct current heating. Have more tests to do...

Defense video for effest 35A 2800mAh (maybe LG HG2 ): https://www.youtube.com/watch?v=dYM80n88Zew
From this test I calculate average 48-55 J/*C but chemistry, environment and current are different.

The Sony VTC5 seems to just edge out the Samsung 25R, but it's literally twice the price and fakes abound. A friend reported the 30Q didn't perform as well as the 25R in his sub-ohm (0.3 or 0.4 ohm from memory) vape.

It's about time someone produced a milli-ohm mod powered by A-spec nanotech

LiPo is not save. If LiPo is in 18650 shell capacity will be near 1Ah... close to LG HB6.
Internal resistance is in close ratio with specific capacity ( mAh/sm^2). Hire is my idealized chart for the best 18650 cells:

Interesting! I would love to see the Aspire ICR "40A" 1800mAh cell added to your Ri vs C graph. It's an astounding performer. Unfortunately it's an ICR cell. :-(

Was that your Efest testing video? Your temperatures are lower than the ones I measured. Measuring near the end of the cell, and not the middle, and through the wrapper means that the temperature of the cell is higher than your measurements. That wrapper is a very effective thermal insulator and that thermal resistance causes a temperature drop across it. The middle of the cell is always hotter than the ends too.

Really glad to see that you used a thermocouple though! So many cell testers use the CBA's temp sensor. But that uses a thermistor, making it essentially useless for measuring anything with more than very slow changing temps. And even more useless for anything with a concave surface...like a battery. There is almost zero thermal coupling between the thermistor bead and the cell. And they cover it in heat shrink too!

 

[Hillhater]

Internal resistance is in close ratio with specific capacity ( mAh/sm^2). Hire is my idealized chart for the best 18650 cells:

Whilst i can see the apparent relationship is clear, and it is useful for clasifying current cells,.. isnt what you have shown the difference between the various cell chemistry's. ?
Technically IR is not a function of "capacity" , just the current status of "power density" for various chemistries/ cell construction.

 

[okashira]

Internal resistance is in close ratio with specific capacity ( mAh/sm^2). Hire is my idealized chart for the best 18650 cells:

Whilst i can see the apparent relationship is clear, and it is useful for clasifying current cells,.. isnt what you have shown the difference between the various cell chemistry's. ?
Technically IR is not a function of "capacity" , just the current status of "power density" for various chemistries/ cell construction.

It can be certainty function of capacity. You can tune anode/cathode physical topology for capacity or surface area (resistance) also thickness of the conductor...

For example compare 25R vs 35E. both NCA.
Seems most NCM is low resistance low cap though. vtc4 vtc5.

 

[Hillhater]

But what does "NCA " really tell us about detail of the cell chemistry ?
its like saying ..a Ferrari and a Toyota are both ICE powered,... but one is much faster than the other.
..and in the battery world , look at our old friend Turnigy LiPo...
..available in versions from 10C to 50C ( same capacity) and same "LiPo" chemistry ?
obviously there are different "blends" of chemistry and details of construction, but we will not be allowed to know the detail.

 

[bellfador]

Interesting! I would love to see the Aspire ICR "40A" 1800mAh cell added to your Ri vs C graph. It's an astounding performer. Unfortunately it's an ICR cell. :-(

Was that your Efest testing video? Your temperatures are lower than the ones I measured. Measuring near the end of the cell, and not the middle, and through the wrapper means that the temperature of the cell is higher than your measurements. That wrapper is a very effective thermal insulator and that thermal resistance causes a temperature drop across it. The middle of the cell is always hotter than the ends too.

Really glad to see that you used a thermocouple though! So many cell testers use the CBA's temp sensor. But that uses a thermistor, making it essentially useless for measuring anything with more than very slow changing temps. And even more useless for anything with a concave surface...like a battery. There is almost zero thermal coupling between the thermistor bead and the cell. And they cover it in heat shrink too!

Sorry for bad English. I not create this video, only watched.
My measurement method is better.
On grafhic Aspire ICR "40A" 1800mAh cell is between VTC4 and HB6.
My chart is idealistic presentation of technological limits in Li-based battery.

 

[BatteryMooch]

Sorry for bad English. I not create this video, only watched.
My measurement method is better.
On grafhic Aspire ICR "40A" 1800mAh cell is between VTC4 and HB6.
My chart is idealistic presentation of technological limits in Li-based battery.

Thanks!

 

[Green Machine]

edit sorry i got this thread confused with my own for sale thread.....