Search found 272 matches

by Pajda
Oct 19 2019 12:34pm
Forum: Battery Technology
Topic: Samsung 40T and other cells like it?
Replies: 93
Views: 2060

Re: Samsung 40T and other cells like it?

Hello, Some months ago I've read somewhere that the Sanyo NCR2070C 20700 3500mAh - 30A is an excellent high power cell with a very good life. Can someone test it to see if it's true? Of course it has lower capacity but it has smaller size also. Maybe it's a good candidate. From my experience I do n...
by Pajda
Oct 09 2019 2:19pm
Forum: Battery Technology
Topic: Samsung 40T and other cells like it?
Replies: 93
Views: 2060

Re: Samsung 40T and other cells like it?

I am not saying that there is no dependency, I am trying to say that there is no general rule to evaluate this dependency (or at least I did not find it). If I use example you can find cell which have after 10% capacity fade ca 30% rise of DCIR (good one) and you can have another cell (with similar ...
by Pajda
Oct 08 2019 1:05pm
Forum: Battery Technology
Topic: Samsung 40T and other cells like it?
Replies: 93
Views: 2060

Re: Samsung 40T and other cells like it?

Well, if we are on the topic... What is the highest capacity I can find in Li Ion cylindrical? (above 21700 of course) Sorry, I do not understand the language of your tribe. You mean what is the biggest cylindrical cell on the market? If you are looking for best absolute energy density in cylindric...
by Pajda
Oct 07 2019 1:19am
Forum: Battery Technology
Topic: Samsung 40T and other cells like it?
Replies: 93
Views: 2060

Re: Samsung 40T and other cells like it?

By the way he asked for 8C discharge cell and 40T can do this, I am thinking that nobody sensible will expect that 40T or similar cell design can do much more than 250 cycles under this continuous load or the discharge end cell temperature will be significantly lower than 80°C. from my tests those ...
by Pajda
Oct 06 2019 2:53pm
Forum: Battery Technology
Topic: Samsung 40T and other cells like it?
Replies: 93
Views: 2060

Re: Samsung 40T and other cells like it?

I don't understand the chart, what are the other IR numbers on the other columns? DCIR IEC is a standardized "two stage method" of measuring DCIR, which requires slightly better equipment to perform, DCIR 10s is "single stage" method, which is very easy to perform, you have to just measure the volt...
by Pajda
Oct 06 2019 2:27am
Forum: Battery Technology
Topic: Samsung 40T and other cells like it?
Replies: 93
Views: 2060

Re: Samsung 40T and other cells like it?

Got this one brand new 40T cell by accident and it reads 7 milliohm internal resistance for a 4Ah cell that is not much bigger than a 18650 (a 21700). Until now I didn't know about it and am looking for an 8C that has better power density than the 25R and this one seems to be it only I read that it...
by Pajda
Sep 30 2019 3:50pm
Forum: Battery Technology
Topic: What Electric Vehicles are using 18650's?
Replies: 6
Views: 350

Re: What Electric Vehicles are using 18650's?

only Tesla Model S and X from the known BEV manufacturers. Rivian and FaradayFuture uses 21700.
by Pajda
Sep 29 2019 4:45am
Forum: Battery Technology
Topic: New 14s battery pack, US18650VTC6 vs NCR18650GA
Replies: 86
Views: 2060

Re: New 14s battery pack, US18650VTC6 vs NCR18650GA

Pajda what is your favorite cell 18650 high discharge long life ? It depends on many factors and applications so there is no clear favorite, but on the other hand, you can't choose completely wrong. If we are talking about 18650 size, "3000 mAh" capacity then we have LG HG2, Samsung 30Q and Sony VT...
by Pajda
Sep 28 2019 12:55pm
Forum: Battery Technology
Topic: New 14s battery pack, US18650VTC6 vs NCR18650GA
Replies: 86
Views: 2060

Re: New 14s battery pack, US18650VTC6 vs NCR18650GA

so far i have detailed data about the 29E(6 and 7), PF, GA, BD, 35E, 25R, MH1 and probably a couple i forgot. and ofcouse a crapload of chinese junk. and my tests are realistic or done on cells that have been in use for years of daily cycles so that is actual usable data and it does give a better i...
by Pajda
Sep 28 2019 12:40pm
Forum: Battery Technology
Topic: New 14s battery pack, US18650VTC6 vs NCR18650GA
Replies: 86
Views: 2060

Re: New 14s battery pack, US18650VTC6 vs NCR18650GA

..this is partially also the reason why tesla still uses a 3350mAh cell in the model S instead of 3500+mAh. it would give a tesla 10kWh extra storage but it would absolutely murder the lifespan of the battery. First I must say, that I have not already tested cells from "100"kWh Tesla battery pack. ...
by Pajda
Sep 28 2019 12:25pm
Forum: Battery Technology
Topic: New 14s battery pack, US18650VTC6 vs NCR18650GA
Replies: 86
Views: 2060

Re: New 14s battery pack, US18650VTC6 vs NCR18650GA

"anything higher capacity will die off quicker" ..... that is only flippy ´s opinion, as he prefers 29E above all. Read again Pajda´s reports. He has biggest collection of really tested cells, bigger than anybody else here. sorry, but its not a opinion, its a measured fact. anyone that has done lif...
by Pajda
Sep 28 2019 11:53am
Forum: Battery Technology
Topic: New 14s battery pack, US18650VTC6 vs NCR18650GA
Replies: 86
Views: 2060

Re: New 14s battery pack, US18650VTC6 vs NCR18650GA

So, only questions remaining, with an average load of 12-14A and short peek loads of ~50A: 1) Will the LG M29, Samsung 29E (E6 that would be, nkon don't have enough E7 in stock), or Panasonic PF perform more or less identical, or does one stand out as a better option (ignore the price)? 2) Will a M...
by Pajda
Sep 20 2019 2:21pm
Forum: Battery Technology
Topic: New 14s battery pack, US18650VTC6 vs NCR18650GA
Replies: 86
Views: 2060

Re: New 14s battery pack, US18650VTC6 vs NCR18650GA

So i'm falling more towards the PF or 29e then, understanding this is a better option then the GA in the long run as they are both cheaper and last longer, with the downside being less initial capacity and more voltage sag. When comparing these two cells, which would be the better one? They cost ex...
by Pajda
Sep 19 2019 3:28pm
Forum: Battery Technology
Topic: New 14s battery pack, US18650VTC6 vs NCR18650GA
Replies: 86
Views: 2060

Re: New 14s battery pack, US18650VTC6 vs NCR18650GA

Thanks that's good to hear. When looking at the datasheet, it shows 70% lifecycle after 500 cycles: https://produktinfo.conrad.com/datenblaetter/1500000-1599999/001558879-da-01-en-LG_LIION_AKKU_INR18650MH1__3200MAH.pdf It's actually less than the NCR18650BD which has close to 80% after 500 cycles? ...
by Pajda
Sep 19 2019 2:44pm
Forum: Battery Technology
Topic: New 14s battery pack, US18650VTC6 vs NCR18650GA
Replies: 86
Views: 2060

Re: New 14s battery pack, US18650VTC6 vs NCR18650GA

Anyway all of the BD,BE,BM line is outdated and there are much better choices for DIYers. What are the better ones which would make sense financially? If you insist on 3200 mAh capacity then it is LG MH1. This cell is used by many ebike producers and it has significantly better operational life tha...
by Pajda
Sep 19 2019 2:20pm
Forum: Battery Technology
Topic: New 14s battery pack, US18650VTC6 vs NCR18650GA
Replies: 86
Views: 2060

Re: New 14s battery pack, US18650VTC6 vs NCR18650GA

I see some of you recommend NCR, and some say forget the GA, so i'm a bit confused.. This contradiction is based on fact, that many users of GA usually does not have comparison with other cells after even few cycles. GA shows very nice parameters under initial capacity/internal resistance test as a...
by Pajda
Sep 19 2019 11:38am
Forum: Battery Technology
Topic: Tesla/Dahn Lithium-NMC532/AG chemistry
Replies: 19
Views: 744

Re: Tesla/Dahn Lithium-NMC532/AG chemistry

.......i just hope that the new generation S has the model 3 cells when they start selling the plaid 3 motor kit. putting down nearly 10.000nm of torques into some poor tires is going to be awesome....... 10,000Nm ! :shock: ....that would truely be more than Awesome ! :lol: Actually it is not extra...
by Pajda
Sep 19 2019 2:27am
Forum: Battery Technology
Topic: New 14s battery pack, US18650VTC6 vs NCR18650GA
Replies: 86
Views: 2060

Re: New 14s battery pack, US18650VTC6 vs NCR18650GA

Isnt the BD basicly the Tesla cell ? Basically yes, I never tested BD to confirm it, but from info what i have the BD seems to be a twin of BE (BE is Tesla cell from original 85 battery) both with older NCA+C chemistry. The only difference is by my opinion that BE does have bottom vent and BD does ...
by Pajda
Sep 05 2019 1:43am
Forum: Battery Technology
Topic: Boston-Power Swing 5300 Li-ion cell test
Replies: 119
Views: 12987

Re: Boston-Power Swing 5300 Li-ion cell test

I finally got that magical 5300mah these cells are advertised at. Of course, as I've pointed out all along, at this discharge rate and voltage levels, there's no real world application that will get you 5300mah. I charged to 4.2v and discharged to 3.75v at .2C. The voltage you see on the LCD is rec...
by Pajda
Sep 01 2019 3:00am
Forum: Battery Technology
Topic: Boston-Power Swing 5300 Li-ion cell test
Replies: 119
Views: 12987

Re: Boston-Power Swing 5300 Li-ion cell test

ElectricGod wrote:
Sep 01 2019 12:25am
.. or 4939 mah per cell is a bit short of 5300mah. The voltages displayed are recovery. The cells discharged down to 2.75v each.
This value is from 4.1V-2.75V range or full range 4.2V-2.75V?
by Pajda
Aug 30 2019 2:30pm
Forum: Battery Technology
Topic: Boston-Power Swing 5300 Li-ion cell test
Replies: 119
Views: 12987

Re: Boston-Power Swing 5300 Li-ion cell test

Does anybody understand what problem does ElectricGod have with Boston cells? He measured capacity 4761 mAh in the range 4.1V-3V with 0.85A discharge current per cell. This equals to ca 90% DoD and this result is completelly fine for this cell. If you need rated capacity from each cell on the market...
by Pajda
Aug 29 2019 2:30pm
Forum: Battery Technology
Topic: Boston-Power Swing 5300 Li-ion cell test
Replies: 119
Views: 12987

Re: Boston-Power Swing 5300 Li-ion cell test

Just for the info. Boston Swing5300 mAh cell, made in China, after two years of resting in paperbox under the table in the office. Nominal capacity test made on $$$..$$ professional battery tester (0.7C charge, 0.2C discharge at 100% DoD 4.2V-2.75V): 5345 mAh / 19.56 Wh / 10s DCIR test at 50% DoD: 2...
by Pajda
Aug 16 2019 1:48pm
Forum: Battery Technology
Topic: Boston-Power Swing 5300 Li-ion cell test
Replies: 119
Views: 12987

Re: Boston-Power Swing 5300 Li-ion cell test

Hmm.. it seems to me that you summarized well known things about Boston Swing. :wink: Yes, the main reason to go with Boston is the price per kWh. One of my favorite suppliers actually offers Boston 5300mAh ca 5% cheaper than NCR18650B 3400mAh in low volume orders.
by Pajda
Aug 14 2019 9:30am
Forum: Battery Technology
Topic: Samsung 29E ver.7 (29E7) 2900mAh cell's capacity test + comparison with 29E ver.6
Replies: 9
Views: 394

Re: Samsung 29E ver.7 (29E7) 2900mAh cell's capacity test + comparison with 29E ver.6

Thanks flippy for the info, LG M29 seems to be slightly better than E6 in cycle life, so E7 should be equal. I did not test E7. I am curious if E7 can match M29 in 1C continuous charge rate cycle life