Search found 458 matches

by Pajda
Jan 10 2022 2:43pm
Forum: Battery Technology
Topic: Cycle life tests of High Energy density cylindrical cells
Replies: 8
Views: 376

Re: Cycle life tests of High Energy density cylindrical cells

can you try eve 26v? They are inside some xiaomi scooter battery packs Probably not in the near future. The reason is that this cell does not fit into the HE or HP category. But that doesn't mean it's a bad choice, it just deserves its own category, something like "good price-performance ratio...
by Pajda
Jan 06 2022 9:44am
Forum: EV Business World
Topic: BYD's LFP blade batteries - heavy but extremely safe.
Replies: 4
Views: 169

Re: BYD's LFP blade batteries - heavy but extremely safe.

Actually, you can already order a sample on Aliexpress. Thanks to the length of 960 mm, it will be a questionable for use elsewhere than in cars or stationary applications.
by Pajda
Jan 05 2022 1:02pm
Forum: Battery Technology
Topic: Cycle life tests of High Energy density cylindrical cells
Replies: 8
Views: 376

Re: Cycle life tests of High Energy density cylindrical cells

added LG M50LT to the test. Q: What to expect in this thread until next christmas? :wink: I would like to add two more cells from 18650 category. The idea is to have one branded cell in each format and two cost@avalability effective alternatives from "less recognized manufacturers(for now)"...
by Pajda
Jan 04 2022 1:49pm
Forum: Battery Technology
Topic: Cycle life tests of High Power density cylindrical cells
Replies: 7
Views: 552

Re: Cycle life tests of High Power density cylindrical cells

I finally found a sample of the cycled VTC6 and added this to the graphs and table. This VTC6 sample lay in a box at room temperature for about 2 years after the end of the 1000 cycle of Standard power rate test and after then the final test for the graphs and table was performed.
by Pajda
Dec 26 2021 8:22am
Forum: Battery Technology
Topic: Cycle life tests of High Energy density cylindrical cells
Replies: 8
Views: 376

Re: Cycle life tests of High Energy density cylindrical cells

From santa, I got a reaction to the previous thread:
We've been following the thread day by day honestly all year, and we only get one new result (and even not fully documented) for that? :cry: :cry: :cry:
I admit my mistake and please take this new thread as a small compensation :wink:
by Pajda
Dec 26 2021 8:15am
Forum: Battery Technology
Topic: Cycle life tests of High Energy density cylindrical cells
Replies: 8
Views: 376

Cycle life tests of High Energy density cylindrical cells

"Standard Power Rate" test (1C continuous discharge) note: the 1C discharge test is performed at ca 90% DoD (4.15V-3.00V) Test eqiupment: - 2pcs ZKETECH EBC-X0510 - BF-2A four-wire cell fixture (10A version with Nickel plated contacts) - tested in room with relatively stable temperature 2...
by Pajda
Dec 24 2021 9:23am
Forum: Battery Technology
Topic: Cycle life tests of High Power density cylindrical cells
Replies: 7
Views: 552

Re: Cycle life tests of High Power density cylindrical cells

"High Power Rate" test (5C continuous discharge) migrated from older thread https://endless-sphere.com/forums/viewtopic.php?f=14&t=103092&start=475#p1606780 note: the 5C discharge test is performed at ca 100% DoD (4.20V-2.50V) Test eqiupment: - 2pcs ZKETECH EBC-A40L - 3pcs ZKETECH...
by Pajda
Dec 24 2021 9:22am
Forum: Battery Technology
Topic: Cycle life tests of High Power density cylindrical cells
Replies: 7
Views: 552

Cycle life tests of High Power density cylindrical cells

"Standard Power Rate" test (1C continuous discharge) note: the 1C discharge test is performed at ca 90% DoD (4.15V-3.00V) Test eqiupment: - 2pcs ZKETECH EBC-X0510 - BF-2A four-wire cell fixture (10A version with Nickel plated contacts) - tested in room with relatively stable temperature 2...
by Pajda
Dec 12 2021 4:40pm
Forum: Battery Technology
Topic: Li-ion cells cycle ageing
Replies: 576
Views: 71424

Re: Li-ion cells cycle ageing

Pajda's Comments and Thoughts (PCT): - Samsung 40T3 finaly reach 1000 cycles, it will now pass the final test on precision tester in TC to complete the data table and then will be inducted into the Hall of Fame. - Samsung 25R8 had a bad start, where due to a faulty data cable I lost the first few da...
by Pajda
Dec 10 2021 7:23am
Forum: Battery Technology
Topic: News from AABC
Replies: 4
Views: 206

Re: News from AABC

I was excited about the GM Ultium battery system. Ultium is a skateboard type platform for GM's EV's. The (flat) battery box contains their modules. The reason it's exciting is that they are designing for second life use, which means that they will be usable for aftermarket applications like ebikes...
by Pajda
Dec 04 2021 3:54pm
Forum: Battery Technology
Topic: Deep Discharge of LI Ion LMO Cells
Replies: 6
Views: 238

Re: Deep Discharge of LI Ion LMO Cells

It depends... I saw a lot cells of different chemistries (NMC, NCA, LFP) discharged below 1V and after recovery they served well like nothing was happened. The most problematic in this case was LCO cells (aka LIPO). So you have these options: 1) throw the battery in the trash 2) try to recover the c...
by Pajda
Dec 04 2021 6:43am
Forum: Battery Technology
Topic: Thread for new battery breakthrough PR releases
Replies: 1778
Views: 282658

Re: Thread for new battery breakthrough PR releases

The main problem with LFP chemistry until recently was really crappy parameters, particularly energy density. For portable electronics are useless even today, but for electric vehicles you need only at least 400 Wh/l and 180 Wh/kg at the cell level (this allows for 200 miles EPA/WLTP range which is ...
by Pajda
Nov 27 2021 6:28am
Forum: Battery Technology
Topic: Li-ion cells cycle ageing
Replies: 576
Views: 71424

Re: Li-ion cells cycle ageing

added updated table and charts for BAK N18650CNP-25 (Nkon) added updated DCIR-10s rise chart Pajda's Comments and Thoughts (PCT): - BAK N18650CNP-25 entered the competition decently. - I managed to pull out of the trash and put another A-20 tester into operation, so three tests can now run simultane...
by Pajda
Nov 17 2021 1:07pm
Forum: Battery Technology
Topic: BAK 18650 CNP 30a 2500mah flat top cell
Replies: 4
Views: 213

Re: BAK 18650 CNP 30a 2500mah flat top cell

CNP is the code name of the cell (BAK N18650CNP 2500 mAh) you asking for?
by Pajda
Nov 17 2021 5:17am
Forum: Battery Technology
Topic: BAK 18650 CNP 30a 2500mah flat top cell
Replies: 4
Views: 213

Re: BAK 18650 CNP 30a 2500mah flat top cell

This BAK CNP cell is a hot candidate for including in my 5C torture test alongside the Samsung 25R8. It may be added just before this Christmas, when the 40T3 test should complete 1000 cycles.
by Pajda
Nov 07 2021 4:53am
Forum: Battery Technology
Topic: When will 4680 cells be available to the public?
Replies: 5
Views: 369

Re: When will 4680 cells be available to the public?

BAK announced 25 Ah in their 4680 sample, which corresponds to the 5x energy announced in Tesla presentation and its on the par with actual 21700/18650. First 21700 production samples also have slightly lower energy density than latest 18650. So yes, pack design will matter the most. It seems that T...
by Pajda
Nov 07 2021 3:53am
Forum: Battery Technology
Topic: Li-ion cells cycle ageing
Replies: 576
Views: 71424

Re: Li-ion cells cycle ageing

Not yet. In general, modern chinese production does not lag significantly behind korean-japanese production. In fact, we can already find cells from chinese companies with better overall parameters. When I look at the EVE 33V datasheet, the presented cycle life at 1C @ 95% DoD corresponds to the bes...
by Pajda
Nov 07 2021 3:30am
Forum: Battery Technology
Topic: When will 4680 cells be available to the public?
Replies: 5
Views: 369

Re: When will 4680 cells be available to the public?

I am curious about the availability and practical usability of 4680 format for applications below 1 kWh. From the beginning of production, I expect even a slightly lower energy density in 4680 than in the latest 18650 and 21700. The greatest step forward I expect in lower internal resistance which s...
by Pajda
Oct 28 2021 12:24pm
Forum: Battery Technology
Topic: Li-ion cells cycle ageing
Replies: 576
Views: 71424

Re: Li-ion cells cycle ageing

that I consider a 100% discharge and huge C-rate to be irrelevant, unrealistically abusive for longevity testing. Yup, It was told at the beginning of this tests. The aim of this test was to show that modern lithium batteries are not as bad as they are still described in old wives' tales spread by ...
by Pajda
Oct 28 2021 4:50am
Forum: Battery Technology
Topic: Li-ion cells cycle ageing
Replies: 576
Views: 71424

Re: Li-ion cells cycle ageing

added updated table and voltage/temperatire charts for Samsung 25R8 (Nkon) Pajda's Comments and Thoughts (PCT): - Samsung 25R8 shows excellent performance at the start (first competitor which can handle 5C 100% DoD discharge test below 50°C) - It will be nice to do comparison with BAK N18650CNP-25, ...
by Pajda
Oct 24 2021 4:36am
Forum: Battery Technology
Topic: Molicel P42a cycle test
Replies: 57
Views: 4090

Re: Molicel P42a cycle test

in my opinion, DCIR has the biggest influence. Batteries that are called li-po in the RC model/drone industry means "a cell that is designed to deliver maximum power at the expense of other features". So both electrochemical and electromechanical design are subject to this. The electromech...
by Pajda
Oct 23 2021 4:42am
Forum: Battery Technology
Topic: Molicel P42a cycle test
Replies: 57
Views: 4090

Re: Molicel P42a cycle test

I am thinking about the voltage response... Do you have experience about this aspect, comparing Lion and Lipo? I mean I would love to know how much delay the P42A will take. Can you set up experiement to measure this? It can be done, but I don't understand in what exactly do you interested? The fig...