Search found 17 matches

by The Battery Doctor
Dec 10, 2017 4:36 am
Forum: Battery Technology
Topic: The 3500mAh heavyweight division: Sanyo NCR18650GA vs Panasonic NCR18650GA vs LG MJ1 vs Samsung INR18650-35E
Replies: 25
Views: 1434

Re: The 3500mAh heavyweight division: Sanyo NCR18650GA vs Panasonic NCR18650GA vs LG MJ1 vs Samsung INR18650-35E

Interesting! I did a test of the same cells including the new Sony US18650VC7, it was published 5 dec. 2017. However i used 40 cells from each brand, as you can see in my data one cell is NOT ENOUGHT for any kind of data cells the capacity can vary between 200-360mAh in brand new cells. If you look ...
by The Battery Doctor
Nov 25, 2017 11:16 am
Forum: Battery Technology
Topic: LG HG6 20650 cell
Replies: 12
Views: 1312

Re: LG HG6 20650 cell

Today i noticed the Sony Konion US18650VC7 was actually released! I order 40 pcs but they are expensive so for testing only. But at low current they can have 3600mah or more!
by The Battery Doctor
Aug 06, 2017 10:39 pm
Forum: Battery Technology
Topic: Disposing of LiPo
Replies: 73
Views: 4411

Re: Disposing of LiPo

in sweden lithium batteries should be placed in the lead acid battery bin. Sweden has a lithiumbattery recycle plant called Scanarc in Hofors where 10-15 million batteries are recycled yearly, they are extracting cobolt from lithium batteries and cobolt and nickel from NIMH batteries. Ive asked them...
by The Battery Doctor
Aug 06, 2017 10:23 pm
Forum: Battery Technology
Topic: Panasonic NCR18650PF
Replies: 7
Views: 730

Re: Panasonic NCR18650PF

The capacity should med tested at 430mA which is mentioned in the datasheet. I always test at 500mAh to get the most accurate capacity. Higher amp = less capacity, since capacity is lost in heat. Also use a geniune imax (Sky RC), a big problem with the fake ones are that the capacity and voltage res...
by The Battery Doctor
Aug 06, 2017 11:40 am
Forum: Battery Technology
Topic: battery authenticity?
Replies: 6
Views: 466

Re: battery authenticity?

Probably, samsung cells are the most counterfeited. Fakes have the same capacity but lower lifetime. Individual stickers on the label and individual packing is a sure givaaway. They come unwrapped in boxes of 100.
by The Battery Doctor
Aug 06, 2017 11:20 am
Forum: Battery Technology
Topic: How many people use 26650's?
Replies: 30
Views: 2199

Re: How many people use 26650's?

I have found genuine 5000 mah 26650 battery cells from china. They are about €50 each so it the price would be better you would only need 20 to build a standard 36V10ah pack and then they would be comparable. I accidentally bought a bunch of 26650 holder so if someone in europe are interested, let m...
by The Battery Doctor
Aug 06, 2017 11:14 am
Forum: Battery Technology
Topic: Bosch Batteries
Replies: 1
Views: 264

Re: Bosch Batteries

Bosch is a closed system, no tampering. They usually use samsung cells (300wh pack). These you can open and you could connect the satiator to measure the capacity. However their later batteries are sealed and tamper proof. No one has ben able to repair them or make copies, yet. I have bought a few 3...
by The Battery Doctor
Aug 06, 2017 11:09 am
Forum: Battery Technology
Topic: Friction stir welding, instead of spot-welding
Replies: 8
Views: 499

Re: Friction stir welding, instead of spot-welding

you are correct, those are "friction stir welds" but they take a lot of time to "weld", cause a lot of heat and can also puncture the cells in the bottom. Also machines ar more likely to be in the $10000 range or more. Looks good but has no application in battery manufacturing, at least not with cyl...
by The Battery Doctor
Aug 06, 2017 11:03 am
Forum: Battery Technology
Topic: A2B battery help needed
Replies: 49
Views: 2060

Re: A2B battery help needed

i have recently (successfully) repaired an A2B main battery (rear) battery successfully. It was a nightmare and took several days. so overthinking the design and so many bad design errors. and they don't seem to last more then 3-4 years and frame batterier cant be bought anymore! Rear batterier cost...
by The Battery Doctor
Aug 06, 2017 7:51 am
Forum: Battery Technology
Topic: multiple chargers for a single battery?
Replies: 6
Views: 430

Re: multiple chargers for a single battery?

My answer is NO. The battery and charger are connected as one unit and they communicate with each other so THAT makes it possible to keep charging CC when the charger need to change to CV and therefor overcharging and damaging the cells! The current vill have nowhere to go and therefor create heat, ...
by The Battery Doctor
Aug 06, 2017 7:45 am
Forum: Battery Technology
Topic: "Fireproof" blanket?
Replies: 6
Views: 486

Re: "Fireproof" blanket?

Its called "fire blanket", are really sheep. its usually white instead of silver. You find them where you buy fire extinguisher. If you need a blanket for a whole bike you might need two. You can attach them with pop rivets.

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by The Battery Doctor
Aug 06, 2017 1:47 am
Forum: Battery Technology
Topic: How to use a 60v battery pack on 48v motor
Replies: 19
Views: 1146

Re: How to use a 60v battery pack on 48v motor

Install a new red discharge wire on the 13th positive cell and disconnect, remove or leave the remaining cells. Now you have 48V =) The charging is trickier, you would have to charge them separately, maby even exchange the BMS in the long run. If you want to use all the remaining cells a "dc to dc c...
by The Battery Doctor
Aug 06, 2017 12:28 am
Forum: Battery Technology
Topic: Mixing 2Pand 3P in 18650 packs.
Replies: 6
Views: 311

Re: Mixing 2Pand 3P in 18650 packs.

I totally agree BUT when i read the title i thought you where going to mix for example 2cells with 3000mah and 3cells with 2000mah, both blocks would be 6000mah. Both would act as a single parallell cell and the voltage dicharge curve SHOULD be similar, assuming they are same chemistry, same amps et...
by The Battery Doctor
Aug 05, 2017 11:51 pm
Forum: Battery Technology
Topic: Do any BMS's balance at 4.1V instead of 4.2V?
Replies: 46
Views: 3111

Re: Do any BMS's balance at 4.1V instead of 4.2V?

BMS can be customized by the manufacturer if you order a MMQ. However the easiest way is it change the charger to a 4.1V charger. My supplyer can offer me custom voltages for only 1-2 dollars more. Also some more fancy chargers has "screw" that can adjust the max voltage. Theoretically the charging ...
by The Battery Doctor
Aug 05, 2017 8:18 pm
Forum: Battery Technology
Topic: I have a problem replacing the battery yamaha pas
Replies: 5
Views: 504

Re: I have a problem replacing the battery yamaha pas

These look identical to the Giant batteriers i worked with. "White wire is ? blue wire is ? yellow wire is ?" are most likely temp sensors/signals to the ebike to display the correct error message in the panel (lov voltage, high temp, low temp). They are usually 0V when not activated and the bike sh...
by The Battery Doctor
Aug 05, 2017 7:59 pm
Forum: Battery Technology
Topic: Charge Two 18v batteries in series with a 36V charger?
Replies: 1
Views: 168

Re: Charge Two 18v batteries in series with a 36V charger?

Its not recommended but if the packs are identical, have the same voltage, and the cells are balanced and both have a proper BMS then the charging would be identical to charging ONE pack.