Cycle life tests of High Power density cylindrical cells

[Souvlucky]

Information on the Molicel P50B from 18650batterystore

 

[neptronix]

Are they two of the same? Or are you seeing one for High Power cells, and one for High Energy?

Frick, i'm wrong, sorry and carry on!

 

[Pajda]

I setup a fundraiser on ko-fi for ES to get our knowledgebase built and it was really, really easy to get the money, as well as have people make the payments.

I'd be willing to throw a few bucks at such a thing.

Thanks for the tip and support, I'll definitely consider it. From my perspective, it would be amazing to find someone who could create an online graphical data viewer with the ability to select specific cells of interest for comparison. Me and possibly other community members would then just pour new data in. Perhaps financial support would help in the search.

 

[Pajda]

Information on the Molicel P50B from 18650batterystore

View attachment 358243

I've already thought about that graph with the temperature rise during cycling too. After switching to the Neware BTS I also have such data available. Only in my tests up to 5C I don't see such a significant temperature increase as Molicel presents here, so it is more a show of temperature fluctuations in my test room .

 

[Bengy22]

-20C charge limit seems pretty good on those P50B's

 

[pomah]

I would love to see what makes it handle those lower temperatures better than current cells, since the chemistry is the same, the tabless design might add something that I dont understand yet.

 

[riba2233]

Also they are not tabless

 

[BlueSwordM]

I would love to see what makes it handle those lower temperatures better than current cells, since the chemistry is the same, the tabless design might add something that I dont understand yet.

High silicon anodes greatly improve low temperature performance, particularly when it's a mixed high silicon-hard carbon-graphite mix.

Higher conductivity electrolytes help considerably as well

 

[pomah]

High silicon anodes greatly improve low temperature performance, particularly when it's a mixed high silicon-hard carbon-graphite mix.

Higher conductivity electrolytes help considerably as well

Where do you see that they have changed chemistry from the normal ncm?

 

[neptronix]

Thanks for the tip and support, I'll definitely consider it. From my perspective, it would be amazing to find someone who could create an online graphical data viewer with the ability to select specific cells of interest for comparison. Me and possibly other community members would then just pour new data in. Perhaps financial support would help in the search.

I could do that but i'm probably too expensive ( 20 years in the field )

I have hired two very good programmers off this site by posting in the help wanted section. It would be a good place to find someone interested in coding that up for ya if/.when the time comes.

 

[BlueSwordM]

Where do you see that they have changed chemistry from the normal ncm?

Ah, this is the trick here.
The cathode isn't what's affected during charging: it's the anode. They've stuck a high performance Si-C anode (not sure if it's Si-Hard Carbon-Graphite or Si-Graphite) in the Molicel P50B, allowing to greatly limit anode polarization during fast charging and especially cold charging.

Make the anode capable of receiving ions quickly enough with a high conductivity electrolyte and you can safely charge a lithium-ion battery in the cold

 

[Souvlucky]

Samsung INR21700-50S(2) has popped up in the Chinese market. Interesting...maybe!

 

[Pajda]

The 50S2 would certainly be worth a try, Samsung has shown in the past that it can significantly improve cycle life between generations.

Otherwise, again added a couple of cycles at 5C test (4C for the 50S) in the third post.

 

[Pajda]

Only a clickbait added a couple of cycles at 5C test (4C for the 50S) in the third post. Cycle life tests of High Power density cylindrical cells Also updated data for Tenpower 40TG here.

Lishen LA, EVE 40P and PL are on the way.

 

[riba2233]

Great news, thanks!

40TG looks surprisingly good, 50S not so much lol

 

[ak136]

A cool video I found for the Ampace tab-less cells:

 

[Pajda]

Lishen LA, EVE 40P and PL arrived few days ago, I have first results showing that there is no significant diffrence between EVE 40PL from (SP) Sample production to (MP) Mass Production model. The 5C dchg-rate cycle life test will start soon.

I think the temperatures obtained in the static ambient air cooling test are a bit misleading, as this setting is sensitive to the quality of the current and associated thermal path from the cell. When measured with forced air cooling, the temperatures came out basically the same.

And as for the disappointing about Lishen LA results, I was advised by the cell supplier that they only have 2 year old cells in stock. The new batch is said to be available later this year.

 

[BlueSwordM]

Lishen LA, EVE 40P and PL arrived few days ago, I have first results showing that there is no significant diffrence between EVE 40PL from (SP) Sample production to (MP) Mass Production model. The 5C dchg-rate cycle life test will start soon.

I think the temperatures obtained in the static ambient air cooling test are a bit misleading, as this setting is sensitive to the quality of the current and associated thermal path from the cell. When measured with forced air cooling, the temperatures came out basically the same.

And as for the disappointing about Lishen LA results, I was advised by the cell supplier that they only have 2 year old cells in stock. The new batch is said to be available later this year.

View attachment 359721
View attachment 359719
View attachment 359720

Oh boy, it looks like the higher electrolyte conductivity, thinner higher power anode and higher interconnect conductivity are more than enough to offset the slight loss of cathode conductivity (thicker cathode) of the P50B.

For others reading, the reason I'm saying this is because the P50B is subjected to 25% higher current loads than the P45B.

 

[Pajda]

updated table and charts with Lishen LA and EVE 40P results at 5C and 10C discharge-rate. Cycle life tests of High Power density cylindrical cells