Search found 255 matches

by leffex
Oct 31 2019 10:25am
Forum: Battery Technology
Topic: Making a small pack 5S24P
Replies: 15
Views: 787

Re: Making a small pack 5S24P

Making another pack. This one has 25p because the cells should measure up to 66ah and so one more is needed in each group beacuse of lower cell capacity.
Difference with this module is that I'm trying more copper in the series connections. 8 instead of 4-5

Image
by leffex
Oct 20 2019 2:20pm
Forum: Items for Sale - Used
Topic: SLX M675 rear disc brake
Replies: 0
Views: 305

SLX M675 rear disc brake

http://uploads.tapatalk-cdn.com/20161126/e44f98281aa04f71eb6d32bad2927ce9.jpg For sale. very good condition used brake with 203mm raiser and disc. Ready to use Shimano SLX M675 hydraulic rear disc brake. One of the best rear brakes with good modulation and performance if used "HARD" Shipping 20 EU....
by leffex
Oct 18 2019 4:16pm
Forum: Battery Technology
Topic: Samsung 40T and other cells like it?
Replies: 93
Views: 2557

Re: Samsung 40T and other cells like it?

Check out VTC5A if you haven't. I came across a graph showing it had higher voltage all the way until emptied @ 20A

Graph here 2,39 in the video:
https://www.youtube.com/watch?v=fZC_bWXrACo
by leffex
Oct 14 2019 7:50pm
Forum: Battery Technology
Topic: Samsung 40T and other cells like it?
Replies: 93
Views: 2557

Re: Samsung 40T and other cells like it?

As for 30C rated cells, don't confuse C with A, many people call 25R a 20C cell when it's a 20A cell with 8C... Hey RG I have some cool info. I tried 10a rated cells, Panasonic 2900pf cells at 24p. Build with copper wire on the series connections. In comparison to some old turnigy multistar 12C 20a...
by leffex
Sep 25 2019 5:40am
Forum: Items for Sale - Used
Topic: retracted no sale.
Replies: 0
Views: 190

retracted no sale.

delete
by leffex
Sep 21 2019 10:45am
Forum: E-Bike Reviews & Testing
Topic: Sabvoton SVMC072150 controller review, variable regen *PICS*
Replies: 332
Views: 56113

Re: Sabvoton SVMC072150 controller review, variable regen *PICS*

So the black on the high speed low speed dongle needs to be connected directly to the negative on the 72v battery? If anyone has their high speed low speed connected and working please let me know how you did it No I don't think so. I had to change some settings turning off some in the bluetooth Th...
by leffex
Sep 20 2019 3:35am
Forum: Battery Technology
Topic: Making a small pack 5S24P
Replies: 15
Views: 787

Re: Making a small pack 5S24P

...So the cell specs call for a .22V voltage drop between .2C and 2C rate. For 5S, that's 1.1V. Interpolating the test results for .2C load, .2*72 = 14A. The observed pack voltage drop at 14A, about .2V, so the perfect world drop is 1.1+.2=1.3V versus the observed 1.9V, a .6V delta. Plus it's reall...
by leffex
Sep 19 2019 5:37pm
Forum: Battery Technology
Topic: Making a small pack 5S24P
Replies: 15
Views: 787

Re: Making a small pack 5S24P

you need way more copper on your bus if you wat better performance. same goes for the inbalance during load. you need way more beefy series connections. What happends when I double or tripple the bus bars? Better performance... Pack module cable are short 10awg 20cm and battery cables are oversize ...
by leffex
Sep 19 2019 11:40am
Forum: Battery Technology
Topic: New 14s battery pack, US18650VTC6 vs NCR18650GA
Replies: 184
Views: 5022

Re: New 14s battery pack, US18650VTC6 vs NCR18650GA

Ok, so if we say that i will have the pack pre-heated to 20c or so before riding off, and ignoring the very few times i'll have to park it outside in the cold, does this change anything as far as what cells are recommended? I see some of you recommend NCR, and some say forget the GA, so i'm a bit c...
by leffex
Sep 19 2019 10:48am
Forum: Battery Technology
Topic: Making a small pack 5S24P
Replies: 15
Views: 787

Re: Making a small pack 5S24P

Just tested module one 5s24p with panasonic PF cells. They have a delta voltage between cells in the module below 0,11v at 3,95v and 150a load. Maybe I didn't balance them so it could even be lower. (Delta voltage between cells at no load was 0,005v) However. Total pack voltage at testing was 19,75v...
by leffex
Sep 17 2019 1:51pm
Forum: Battery Technology
Topic: BMS broken, damaged cells, or both?
Replies: 59
Views: 1178

Re: BMS broken, damaged cells, or both?

It would be easier if you mesured one cell group at a time, to get the voltages. ... Hi Leffex, With this low voltages of my pack.. Except for the bms, do you think any of the batteries still can be used, or should I consider it as total loss? Greetings Bas I think you should double check voltages ...
by leffex
Sep 16 2019 2:32pm
Forum: Battery Technology
Topic: Making a small pack 5S24P
Replies: 15
Views: 787

Re: Making a small pack 5S24P

I searched for a box that fits the space I want to use and put my battery into. I can put 4 of them into my space so I started with ordering 2 boxes to try. Ordered another two from here: https://www.aliexpress.com/item/33004388619.html?spm=a2g0o.cart.0.0.77773c00w03GYq&mp=1 How do you find the righ...
by leffex
Sep 16 2019 1:06pm
Forum: Battery Technology
Topic: BMS broken, damaged cells, or both?
Replies: 59
Views: 1178

Re: BMS broken, damaged cells, or both?

In this picture, the iron connection part on top is a little loose, when I press it, I can see it touch and untouch. Could that.. Be.. The.. Reason? EDIT: More pics of other side of the Pack. You need to repair it if its broken or it may cause danger in the future if you let it be. You use alot of ...
by leffex
Sep 15 2019 11:37am
Forum: Battery Technology
Topic: Pen size spot welder
Replies: 3
Views: 184

Re: Pen size spot welder

I saw it too.

I guess you still need all the normal extras
by leffex
Sep 14 2019 1:34pm
Forum: Battery Technology
Topic: Making a small pack 5S24P
Replies: 15
Views: 787

Re: Making a small pack 5S24P

Another pack mocked up for photos: https://i.imgur.com/7MzkxJc.jpg https://i.imgur.com/q5RSl0X.jpg Module 2 pack stats: 18,5cm*7,5cm*30cm = 4162cm^3 Volume = 4,162 L 5s*26p 26F nominal 1196wh 1196wh / 4,162 L = 287wh/L Power rating 26p x 5,2a = 135,2A I'm thinking about what these modules can give i...
by leffex
Sep 01 2019 3:42pm
Forum: Motor Technology
Topic: QS-motor phase wire upgrade + Sabvoton 350A
Replies: 6
Views: 385

Re: QS-motor phase wire upgrade + Sabvoton 350A

High average consumptions is 63w energy used per km in distance

But I like that I use alot less (I have a higher efficiency) while accelerating and when using higher power but not so much in slow riding conditions rather than other positive aspects.
by leffex
Sep 01 2019 1:49pm
Forum: Motor Technology
Topic: QS-motor phase wire upgrade + Sabvoton 350A
Replies: 6
Views: 385

Re: QS-motor phase wire upgrade + Sabvoton 350A

A sidenote ... Yeah that is pretty interesting. thanks! What I mean it is pretty good to get 5% more range after fixing new cables? estimate and guesses I have RC cells but replacing with 5s24p 18650pf block. So it will get 2,4x less resistance than you calculated :P https://endless-sphere.com/foru...
by leffex
Aug 30 2019 1:08pm
Forum: Motor Technology
Topic: QS-motor phase wire upgrade + Sabvoton 350A
Replies: 6
Views: 385

QS-motor phase wire upgrade + Sabvoton 350A

Hey I want to know what benefit I get from thicker phase wires vs original thin wire in performance measures. Also positive and negative battery wires are replaced. I know the resistance in the wire is less and the voltage drop is less because of that. What performance gain in power and effeciency d...
by leffex
Aug 27 2019 12:54pm
Forum: Battery Technology
Topic: Making a small pack 5S24P
Replies: 15
Views: 787

Re: Making a small pack 5S24P

Something like cylindrical or 6squared plastic cell holders. The ones I used was 1x4p so I added them together and broke some to make smaller pieces were needed These are very alike but not the ones I have https://vruzend.com/product/hexagonal-18650-battery-holders-3-cell/ I first thought not of usi...
by leffex
Aug 24 2019 9:59am
Forum: Battery Technology
Topic: Making a small pack 5S24P
Replies: 15
Views: 787

Re: Making a small pack 5S24P

Work table: https://i.imgur.com/o3WyCNJ.jpg 1 of 5 pieces https://i.imgur.com/8rObp1F.jpg 5 pieces fits inside one https://i.imgur.com/OHpeWNe.jpg Finished pack: https://i.imgur.com/ONDnoex.jpg https://i.imgur.com/6ZqiWck.jpg Module pack stats: 18,5cm*7,5cm*30cm = 4162cm^3 Volume = 4,162 L 5s*24p 2,...
by leffex
Aug 05 2019 1:09pm
Forum: E-Bike General Discussion
Topic: Noob expat in Sweden attempting a first build
Replies: 11
Views: 456

Re: Noob expat in Sweden attempting a first build

just search elcykelkit nor elcykelbatteri and you will find front wheel motor or battery in Sweden with warranty.

Tax for buying outside eu is + 3-8% for ebike parts into Sweden and +25% tax on that aswell as +100 sek fee for handling.
by leffex
Aug 01 2019 1:36pm
Forum: Battery Technology
Topic: 0-120V 0-30A variable rectifier/amps/charger, is it ok?
Replies: 12
Views: 465

Re: 0-120V 0-30A variable rectifier/amps/charger, is it ok?

Yes its awesome and works perfectly :banana: :banana: :banana: :banana: :banana: 5/5 Have you got one of these Leffex? If you do what voltages and currents have you tried? Is the output stable and reliable? I have tried it at maximum about 92,5v charging at 20-25A. So I guess the maximum is either ...
by leffex
Jul 31 2019 6:04pm
Forum: Battery Technology
Topic: 0-120V 0-30A variable rectifier/amps/charger, is it ok?
Replies: 12
Views: 465

Re: 0-120V 0-30A variable rectifier/smps/charger, is it ok?

Yes its awesome and works perfectly :banana: :banana: :banana: :banana: :banana: 5/5 Have you got one of these Leffex? If you do what voltages and currents have you tried? Is the output stable and reliable? I have tried it at maximum about 92,5v charging at 20-25A. So I guess the maximum is either ...
by leffex
Jul 31 2019 6:00pm
Forum: Battery Technology
Topic: 0-120V 0-30A variable rectifier/amps/charger, is it ok?
Replies: 12
Views: 465

Re: 0-120V 0-30A variable rectifier/amps/charger, is it ok?

The charger is based on R4850G

R4850G looks about like this inside:
viewtopic.php?t=86038
by leffex
Jul 31 2019 5:50pm
Forum: Battery Technology
Topic: 0-120V 0-30A variable rectifier/amps/charger, is it ok?
Replies: 12
Views: 465

Re: 0-120V 0-30A variable rectifier/amps/charger, is it ok?

Yes true. Charging only under on-sight as well. I use a 88v charger changed to about 90,5v. and about 5a The charger looks like this: https://www.aliexpress.com/item/32994268747.html?spm=a2g0o.productlist.0.0.699721a1NysN6Y&algo_pvid=f9c7a566-defb-47b8-aaae-266bb5e5e3a7&algo_expid=f9c7a566-defb-47b8...