Search found 211 matches

by thunderheart
Oct 01 2019 3:15pm
Forum: Battery Technology
Topic: Sony VTC5 test + comparison with Samsung 25R
Replies: 2
Views: 216

Sony VTC5 test + comparison with Samsung 25R

Sony VTC5 or US18650VTC5 is a 2600mAh 18650-size Li-ion cell which supports continuous discharge at up to 30A with 80°C temperature cut or up to 20A with no temperature control. VTC5 can hold up to 100A pulse discharge for <3 seconds. https://ic.pics.livejournal.com/thunderheartrev/71546108/274196/2...
by thunderheart
Sep 06 2019 1:26pm
Forum: Battery Technology
Topic: Boston-Power Swing 5300 Li-ion cell test
Replies: 119
Views: 12922

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

You know what? I really love this culture of discussion full of respect to each other. It's a pleasure to read you comments, guys! :thumb:
by thunderheart
Sep 04 2019 5:38pm
Forum: Battery Technology
Topic: Queen Battery QB26650-2300 LiFePO4 cell's test + comparison with A123 Systems ANR26650M1B
Replies: 5
Views: 234

Re: Queen Battery QB26650-2300 LiFePO4 cell's test + comparison with A123 Systems ANR26650M1B

john61ct wrote:
Sep 04 2019 5:30pm
I don't see any QB direct site with shopping functionality
You drop them an e-mail, discuss the order details, the price, then pay by PayPal. Their prices are higher on Ali due to Ali's fees.
by thunderheart
Sep 04 2019 3:57pm
Forum: Battery Technology
Topic: Queen Battery QB26650-2300 LiFePO4 cell's test + comparison with A123 Systems ANR26650M1B
Replies: 5
Views: 234

Re: Queen Battery QB26650-2300 LiFePO4 cell's test + comparison with A123 Systems ANR26650M1B

Why would they restrict serialing to 4S 12V maximum? I wasn't able to get any reasonable answer from them. I think they just allow wide margin of IR for a batch but the cells i got have very low difference and fluctation. Even lower than 2500mAh cells. So i think there is no real reason behind that...
by thunderheart
Sep 04 2019 3:38pm
Forum: Battery Technology
Topic: Boston-Power Swing 5300 Li-ion cell test
Replies: 119
Views: 12922

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

Hillhater wrote:
Sep 03 2019 6:47pm
thunderheart wrote:
Sep 03 2019 1:32pm
..
....
So in 3.0-2.75V range there is only 66mAh or 1.24% of capacity stored.
Yes... but only at 0.2C discharge.
If you look at the data for 2.5C (13A) discharge there is significant capacity (10+%) below 3.0v
..at the cost of cycle life !
Exactly. 13.7% at 13A.
by thunderheart
Sep 03 2019 4:10pm
Forum: Battery Technology
Topic: Queen Battery QB26650-2300 LiFePO4 cell's test + comparison with A123 Systems ANR26650M1B
Replies: 5
Views: 234

Queen Battery QB26650-2300 LiFePO4 cell's test + comparison with A123 Systems ANR26650M1B

QB26650-2300 is the second LiFePO4 model from Queen Battery. The 2500mAh cell i tested recently and i'll compare the two QB models to A123 Systems ANR26650M1B Grade A and Grade B cells. https://ic.pics.livejournal.com/thunderheartrev/71546108/271173/271173_original.jpg The battery was bought from my...
by thunderheart
Sep 03 2019 1:32pm
Forum: Battery Technology
Topic: Boston-Power Swing 5300 Li-ion cell test
Replies: 119
Views: 12922

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

What a discussion, guys! Love things like that! So, here is the 0.2C/1.06A discharge map starting at 4.179V (the voltage of the cell charged to 4.20V/100mA cut-off and left 1hr): 4.1V: 98mAh 4.0V: 552mAh 3.9V: 1004mAh 3.8V: 1527mAh 3.7V: 2027mAh 3.6V: 2763mAh 3.5V: 3850mAh 3.4V: 4575mAh 3.3V: 4966mA...
by thunderheart
Aug 22 2019 8:32am
Forum: Battery Technology
Topic: Queen Battery QB18350 900mAh 9A Li-ion cell's capacity test
Replies: 2
Views: 152

Re: Queen Battery QB18350 900mAh 9A Li-ion cell's capacity test

Headrc wrote:
Aug 22 2019 8:26am
The best go-to guy that I have found for battery reviews! Thanks Thunderheart
Thanks Headrc!:)
by thunderheart
Aug 22 2019 3:26am
Forum: Battery Technology
Topic: Queen Battery QB18350 900mAh 9A Li-ion cell's capacity test
Replies: 2
Views: 152

Queen Battery QB18350 900mAh 9A Li-ion cell's capacity test

I've tested cylindrical cells of different sizes - from 10440 to 28600, but it's the first time i've got an 18350 cell. Queen Battery QB18350 is a 900mAh cell rated at 9A max. https://ic.pics.livejournal.com/thunderheartrev/71546108/270044/270044_original.jpg It has the same 18mm diameter as any 186...
by thunderheart
Aug 20 2019 6:26am
Forum: Battery Technology
Topic: Boston-Power Swing 5300 Li-ion cell test
Replies: 119
Views: 12922

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

Shunt wrote:
Aug 20 2019 1:41am
The positive end does have a nickel strip professionally welded in place to solve that problem
Image
by thunderheart
Aug 19 2019 2:04am
Forum: Battery Technology
Topic: Li-ion smart charger recomendation?
Replies: 12
Views: 310

Re: Li-ion smart charger recomendation?

Try Miboxer C4-12 if you need a charger (not discharger). Revived some 0V cells with it. Excellent monster I just checked out that link, and it seems like that's what I'm looking for. One disadvantage is that it will not discharge. Is this a problem, or do you know of another unit that has all the ...
by thunderheart
Aug 18 2019 5:05pm
Forum: Battery Technology
Topic: Li-ion smart charger recomendation?
Replies: 12
Views: 310

Re: Li-ion smart charger recomendation?

Try Miboxer C4-12 if you need a charger (not discharger). Revived some 0V cells with it. Excellent monster
by thunderheart
Aug 16 2019 5:20pm
Forum: Battery Technology
Topic: Boston-Power Swing 5300 Li-ion cell test
Replies: 119
Views: 12922

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

ElectricGod wrote:
Aug 16 2019 1:14pm
What would I get for the Boston cells?
3000 cycles at 80% DOD
by thunderheart
Aug 15 2019 1:30pm
Forum: Battery Technology
Topic: Nicad vs Nimh for electric start
Replies: 17
Views: 491

Re: Nicad vs Nimh for electric start

Why not use A123 26650 LiFePo4 cells? 4S is a popular drop-in replacement for 12V starting batteries. They long-lived, high quality and out out lots of amps. You read my thoughts!!! High-drain LiFePO4 cells like A123 ANR26650M1B ( my test ) or QB26650-2500 ( my test ) are ideal for starter batterie...
by thunderheart
Aug 14 2019 6:02am
Forum: Battery Technology
Topic: Samsung 29E ver.7 (29E7) 2900mAh cell's capacity test + comparison with 29E ver.6
Replies: 9
Views: 391

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

Less than a month ago i tested Samsung 29E v.6 which many people say is a better cell than the v.7. This time i've tested the v.7 cell and compared them to find out where is the truth. Just to remind, Samsung 29E is a 2900mAh 18650-size cell which supports discharge at up to 5.5A. https://ic.pics.li...
by thunderheart
Aug 10 2019 6:38am
Forum: Battery Technology
Topic: LG M50T Grade A high capacity 5000mAh 21700 cell's test
Replies: 10
Views: 661

Re: LG M50T Grade A high capacity 5000mAh 21700 cell's test

Thanks for sharing, Pajda! It's a very important info!
by thunderheart
Aug 09 2019 10:46am
Forum: Battery Technology
Topic: LG M50T Grade A high capacity 5000mAh 21700 cell's test
Replies: 10
Views: 661

Re: LG M50T Grade A high capacity 5000mAh 21700 cell's test

Yeah, it should be $0.4-0.5 cheaper than 50E but is that economy worth the difference in cycle life? For those who build packs for sale - yes. They need numbers. The bigger is the capacity - the higher is the price tag. But for DIY battery makers cycle life plays an important role i think.
by thunderheart
Aug 09 2019 10:18am
Forum: Battery Technology
Topic: LG M50T Grade A high capacity 5000mAh 21700 cell's test
Replies: 10
Views: 661

Re: LG M50T Grade A high capacity 5000mAh 21700 cell's test

Hi neptronix ! I'm more worried with its poor cycle life. Only 300 cycles down to 80% are guaranteed using quite low 0.33C charge/discharge. So even at 0.5C continuous discharge which you recommend it won't last long (theoretically). If the real life experience isn't better - it would be a disappoin...
by thunderheart
Aug 09 2019 6:20am
Forum: Battery Technology
Topic: LG M50T Grade A high capacity 5000mAh 21700 cell's test
Replies: 10
Views: 661

LG M50T Grade A high capacity 5000mAh 21700 cell's test

LG INR21700 M50T is a 5000mAh Li-ion cell of 21700 size (also known as 2170). LG M50T was previously known as M50 (without T) and even in the tentative version of the datasheet the model name was M50. More than a year ago i tested it (Grade B) and compared with Samsung 48G but then i was using v2.5 ...
by thunderheart
Aug 05 2019 1:01am
Forum: Battery Technology
Topic: Charging 14s pack with 13s charger
Replies: 3
Views: 172

Re: Charging 14s pack with 13s charger

If I were to charge a 14s pack with a charger built for 13s (54.6V), any idea how much capacity would I be giving up? Is there any problem/danger doing this? I assume each cell would be at about 3.9V instead of 4.2V. I realize I will need to periodically charge with a 52V charger to balance the pac...
by thunderheart
Aug 02 2019 5:59pm
Forum: Battery Technology
Topic: Capacity test: Queen Battery QB18650 2000mAh 20A high-drain cell which surprised me
Replies: 2
Views: 199

Capacity test: Queen Battery QB18650 2000mAh 20A high-drain cell which surprised me

This is the 3rd 18650-size model in Queen Battery's lineup. I've already tested the 3000mAh low-drain and 2600mAh mid-drain ones. This one is rated at 2000mAh and supports continuous discharge at up to 20A. https://ic.pics.livejournal.com/thunderheartrev/71546108/264813/264813_original.jpg The batte...
by thunderheart
Jul 29 2019 4:59pm
Forum: Battery Technology
Topic: Awesome study / information on NCA battery degradation (Panasonic NCR18650PD)
Replies: 16
Views: 821

Re: Awesome study / information on NCA battery degradation (Panasonic NCR18650PD)

geekmystique wrote:
Jul 27 2019 3:54pm
If sensibly used, NCA cells should last well over 10 years and over 1000 cycles with still around 80% original capacity left (WOOHOO)
LiFePO4 cells would do better even if used careless + they support charging/discharging at wider temperature range.
by thunderheart
Jul 27 2019 2:09am
Forum: Battery Technology
Topic: Queen Battery QB26650-2500 LiFePO4 cell's test + comparison with A123 Systems ANR26650M1B
Replies: 6
Views: 304

Re: Queen Battery QB26650-2500 LiFePO4 cell's test + comparison with A123 Systems ANR26650M1B

neptronix wrote:
Jul 26 2019 7:45pm
You know what they would be fantastic for? they'd make a hell of a 12V car/motorcycle starter battery.
Bingo! If they were available 6 months ago i'd buy them instead of ANR26650M1Bs...
john61ct wrote:
Jul 26 2019 9:53pm
And safety all-important
And cycle life...