Search found 62 matches

by DrKraut
Jul 07 2019 8:05am
Forum: Battery Technology
Topic: Bluetooth DC energy monitor
Replies: 44
Views: 2376

Re: Bluetooth DC energy monitor

Awesome project, I think lots of people are looking for BL power meters!
Great work you're doing here :bolt:
by DrKraut
Jun 12 2019 3:19pm
Forum: Battery Technology
Topic: Which cell for long lasting battery
Replies: 32
Views: 1516

Re: Which cell for long lasting battery

Been running Headway 40152S 15Ah LiFePO4 for 6 1/2 years. Over 800 cycles of daily use. They are at 80% of original capacity but sag really bad now. 10 years is probably out of reach for today's 18650's. LTO might do it for you, but it hasn't been used enough around here enough to know for sure. It...
by DrKraut
Jun 12 2019 3:18pm
Forum: Battery Technology
Topic: Which cell for long lasting battery
Replies: 32
Views: 1516

Re: Which cell for long lasting battery

Hi, Thanks for detailed destription of your experience with LG MG1 based battery. I can just say that the MG1 cells performs in your application exactly as I expected and it confirms my laboratory cycle life tests of this particular LG chem cell. LG MG1 is my personal favourite for the most shitty ...
by DrKraut
Jun 12 2019 3:10pm
Forum: Battery Technology
Topic: Which cell for long lasting battery
Replies: 32
Views: 1516

Re: Which cell for long lasting battery

A) Can you please describe in details how did you measure battery capacity at the beginning and after 170 cycles ? B) Where did you buy the cells ? A rough measure always was that I could ride to work, which are 52km total and another 15km until it was empty. As time passed I could barely go to wor...
by DrKraut
Jun 12 2019 2:57pm
Forum: Battery Technology
Topic: Which cell for long lasting battery
Replies: 32
Views: 1516

Re: Which cell for long lasting battery

Not same termination profile. Each factory run differs. Each lab test run will differ. Point is no on should be using this data to set their own usage patterns in real life. Don't charge that fast, Do not use that high a V setpoint. Do not hold CV that long. Do not discharge that low. What do you m...
by DrKraut
Jun 10 2019 1:41pm
Forum: Battery Technology
Topic: Which cell for long lasting battery
Replies: 32
Views: 1516

Re: Which cell for long lasting battery

I just found something interesting while digging around: Its about the Sammy 35E cell but anyway really suspicious or strange: From this datasheet http://downloads.cdn.re-in.de/1400000-1499999/001499572-da-01-de-SAMSUNG_LI_ION_AKKU_18650__3500MAH_10A.pdf Thats the cycle life stats: inr18650-35E cycl...
by DrKraut
Jun 10 2019 10:21am
Forum: Battery Technology
Topic: Which cell for long lasting battery
Replies: 32
Views: 1516

Re: Which cell for long lasting battery

I tought that too at my first design phase for the battery. But I'm limited to the triangle size of my bike. Which just fits about 91 cells plus the controller. So i have to stay high energy density cells, since I can't charge at work.
by DrKraut
Jun 10 2019 7:43am
Forum: Battery Technology
Topic: Which cell for long lasting battery
Replies: 32
Views: 1516

Which cell for long lasting battery

Hey guys, at the moment i have a 7P13S battery consisting of 91 LG MG1 and after only about 170 cycles it lost already about 40%. I tested it multiple times and its quite disappointing. My setup looks like following: Charge overnight with about 3A or 0,3C. Commuting to work and back, each way is abo...
by DrKraut
Oct 02 2016 1:39pm
Forum: Items for Sale - New
Topic: CHEAP NEW ORIGINAL CELLS LI-ION 18650
Replies: 787
Views: 196746

Re: BRAND NEW CELLS 18650 SAMSUNG/SANYO/PANASONIC/LG

I also ordered 140x Sanyo GAs for a project, everything went flawless. Including very good packaging.
Big thumps up for your good service and good prices!
by DrKraut
Aug 27 2016 2:57am
Forum: Items for Sale - New
Topic: CHEAP NEW ORIGINAL CELLS LI-ION 18650
Replies: 787
Views: 196746

Re: BRAND NEW CELLS 18650 SAMSUNG/SANYO/PANASONIC/LG

I need to say some good words on tumich. I ordered multiple times from him, everyting went so easy, it couldn't be better. This time i got the cells within 72h !!! Really great service.
by DrKraut
Oct 03 2015 1:32am
Forum: E-Bike Technical
Topic: Which rear-geared-drive for bike that has 8 rear speeds?
Replies: 80
Views: 4545

Re: Which rear-geared-drive for bike that has 8 rear speeds?

I've read the whole thread but i'm not sure about the motor windings.
Does the 36V 201 and the 48V 201 have the same torque output?
If yes i would run the 36V at 48V battery for more speed and torque
by DrKraut
Jul 23 2015 8:41am
Forum: E-Bike Build Threads / Photos & Video
Topic: Super Commuter: 6T MAC 48V/120A Kelly in a 26" rim
Replies: 62
Views: 16707

Re: Super Commuter: 6T MAC 48V/120A Kelly in a 26" rim

Very fine build ! 8)
I also live in Germany and asked myself if you are not scared to ride in cities with such a bike. You know its not legal without a license :lol: ?
What's your plan if the cops stop you?
by DrKraut
Jul 17 2015 4:19am
Forum: E-Bike Build Threads / Photos & Video
Topic: Moonshine's Vector/MXUS/MaxE Build
Replies: 229
Views: 28815

Re: Moonshine's Vector/MXUS/MaxE Build

I'm also going to build a vector, and saw the chainline problem.
So you use a multi speed freewheel and a chain tensioner, how do you secure the chain so it doesn't change gear itself?

BTW very nice build 8)
by DrKraut
Jul 16 2015 11:10am
Forum: Battery Technology
Topic: Zero MX 2012 Battery Build
Replies: 11
Views: 810

Re: Zero MX 2012 Battery Build

Thank you all, helped very much :)
by DrKraut
Jul 13 2015 1:43pm
Forum: Items for Sale - New
Topic: Vector Storm e-bike Frame 299€ / Parts WORLDWIDE
Replies: 2352
Views: 342095

Re: Vector e-bike Frame 625$ /MAX-E/FORK/SHOCK/MOTOR/BATTERY

Does Artur answer you PMs? He isn't on mines :(
I really need a frame in the next weeks
by DrKraut
Jul 13 2015 1:27pm
Forum: Battery Technology
Topic: Turnigy multistar vs. Samsung 25R
Replies: 29
Views: 4292

Re: Turnigy multistar vs. Samsung 25R

I just want to add a little story from me I'm an electronics engineer and 2 years ago i started to build my first ebike. At that time i didn't had too much knowledge about batteries, but i knew i want 18650 since they seemed to be way more safe. Lifepo wasn't a choice for me since its really heavy. ...
by DrKraut
Jul 13 2015 2:04am
Forum: E-Scooter and Motorcycle General Discussion
Topic: Zero MX without battery
Replies: 1
Views: 525

Zero MX without battery

Hey guys,
i want to build a new battery for a zero mx and need to by a zero mx without a battery. But i really jas everything else like agni an alltrax and such.
My question is how much should i pay for it on a european market.

Thanks :)
by DrKraut
Jul 12 2015 5:38pm
Forum: Motor Technology
Topic: STP 75NF20 false alarm. it has 28mohm Rdson
Replies: 8
Views: 811

Re: Is STP 75NF20 better mosfet choice than IRFB4115 ?

These fets are not 2.8mOhm but 28mOhm according to the official ST datasheet!
:O
by DrKraut
Jul 11 2015 2:07pm
Forum: Battery Technology
Topic: Can hk lipo be beaten for this application?
Replies: 40
Views: 4015

Re: Can hk lipo be beaten for this application?

Wiht 18650 i mean, powerful cells like the Samsung 25R or the Sony VTCs with really low IR. They are way lighter than lipo,have bettery cycle life, are safe and just a tad more expensive. But if you really want high power, you only have the LiPo choice with 130C peak cells. But that amount of power ...
by DrKraut
Jul 11 2015 6:13am
Forum: Battery Technology
Topic: Zero MX 2012 Battery Build
Replies: 11
Views: 810

Re: Zero MX 2012 Battery Build

The 550A are just peak for max. 10 sec.
Continuously the controller only draws 200A which are about 12A per cell, so no problem about that. But if i can i will reduce peak to 500Aor 450A
35P would be to heavy and expensive
by DrKraut
Jul 11 2015 4:09am
Forum: Battery Technology
Topic: Can hk lipo be beaten for this application?
Replies: 40
Views: 4015

Re: Can hk lipo be beaten for this application?

The first three are not LifePO but Lithium Ion with NCA Kathode from Samsung. But the 29E is way to weak. You need at least 6C if you only want a 1kWh pack. My suggestion would be using 18650 cells, because any kind of LiPo pouch is very sensitive and the HK is just bad quality and overrated and als...
by DrKraut
Jul 11 2015 3:21am
Forum: Battery Technology
Topic: Zero MX 2012 Battery Build
Replies: 11
Views: 810

Re: Zero MX 2012 Battery Build

Thank you very much guys, my plan is to use Samsung 25R in 18S18P configuration. I'm going to charge to 4.1V or 74V, internal resistance of the whole battery pack should be less than 25mOhm ! Can i really put 550A peak at 72V into the Agni of the MX ? That sounds really high to me, i might reduce it...
by DrKraut
Jul 10 2015 4:34pm
Forum: Battery Technology
Topic: Zero MX 2012 Battery Build
Replies: 11
Views: 810

Re: Zero MX 2012 Battery Build

I'm aware of all that, since i study electronic engineering. But in cant find any information about the battery wich is labeled as ZF3. I only know they use 14 cells and the nominal capacity is 3kWh. Also are they using the Agni 95 or a Perm Motor, no idea. I would any information really appreciate :)
by DrKraut
Jul 10 2015 11:19am
Forum: Battery Technology
Topic: Zero MX 2012 Battery Build
Replies: 11
Views: 810

Zero MX 2012 Battery Build

Hey guys, i have a Zero MX 2012 without a battery.So i need to build a battery for it. Does anybody know how much Ah they have. I figured out it has 14 cells in series. But dont know the exact Ah but at 3kWh it would be around 60Ah Also very important, how much Amperes does the BMS draw from the Bat...
by DrKraut
Jul 05 2015 8:31am
Forum: E-Bike Non-hub Motor Drives
Topic: BIG BLOCK alternative Motor
Replies: 452
Views: 88942

Re: BIG BLOCK alternative Motor

So were can i get cheap sprockets for 420 chain ?