Samsung 25R/LG 18650HE2/ Sony VTC5 high power 18650 battery

[Ebikebert]

yes sir you are correct i will be running two 12 awg solid copper wires across the 10 cells to put them in series. There will be pictures to come soon.

 

[district9prawn]

I just got a quote of 4.3usd each LG 18650HE2 cell for a 100pc order, confirmed that they are the 35amp version. Too good to be true or some kind of catch maybe? They seem like a legit company on alibaba, linked below. I also inquired about panasonic 3.4ah cells and they sent me a picture of them with a made in china sticker, from reviews I read they stated made in Japan. Lower quality maybe?

I got my cells with similar stickers on them when I bought a bunch from alibaba. Seller claimed it was a shipping requirement for aH and voltage to be clearly labelled on every cell. Perhaps this ties in to the new wH shipping restrictions as well. Cells are as expected though.

 

[Ebikebert]

Sorry guys i have been really busy with school and ran out of solder! I just bought some yesterday and as soon as i get it in the mail i will resume the build.

 

[Dark Knight]

Gonna be keeping my eye on this - subscribed.

 

[ecruz]

I am building the same thing just bigger. Have you looked into one of these? I just received mine. 220V/110V Micro Spot Welding Machine Battery Spot Welder dual pulse US I bought mine on ebay for $186 shipped. Have you decided on a bms? Check out www.Besttechpower.com Also remember when you put four cells in parallel your amps with double by each cell. So if you have 4 that would be 120amps. So your battery will not be working so hard.

 

[Ebikebert]

Good to hear that you will be using these excellent cells. I did not want to buy a welder and did not have the money to buy one. I have pretty good soldering skills and already put all of my cells in series. All i have left now is to put the balance wires and main leads onto the cells and then heat shrink it all together. I would not push these cells beyond 20 amps per cell because after you go over 20 amps per cell you are just eating your cycles of life. If you keep it below this discharge rate you will ensure you have a long lasting pack. Pictures soon to come on how i put the cells in series with my custom made battery tabs.

 

[sflorlando]

Ecruz,

Let me know how you like that spot welder. I wouldn't mind spending upwards close to $500 for a quality one, but unable to find a good model.

Ken

 

[ecruz]

I am waiting to get the batteries I need to swap the Panasonic 18650B for the Sony VTC5. I am waiting on my vendor to swap them out to try the welder. It is made cheap in the sense as its not pretty but materials are ok. I am tempted to try it on older cells but they are still working and need them for my flahslights lol. Do you guys like the VTC5 over the Samsung's I am planning on a 22s10p with bms. I need the pack to be able to go as high as 60-80amp as the Cromotor v3 is amp hungry. I will probably start my own thread when constructions begin.

 

[Ebikebert]

yes please do start a thread i want to see your build maybe some day in person too.

 

[ecruz]

Oh wow, just realized your in Fl. Very cool sure we can go riding! Well if the spot welder does the job I can sell it to you after since its a one time use kind of thing. I figure by the time the battery pack needs rebuilding there will be some new Lithium-bacterial self reproducing nano technology available. LOL

 

[Ebikebert]

progress pics, Ugly soldering I know but it did the job :wink:

 

[Ebikebert]

cool man sounds good, I tried to get a group together but i don't know what happened lol http://endless-sphere.com/forums/viewtopic.php?f=3&t=58859 . Its funny you mention nano-technology that is what im going to start studying for this year at the new engineering school in lakeland.

 

[Ebikebert]

The battery and charger wil be mounted in the pelican case on the bike! I also made a quick release so i could take the battery pack with me wherever and charge it as i go.

 

[sflorlando]

cool bike!

Ya spot welder deal sounds good. As long as it works well.

Ken

 

[ecruz]

Well after posting that I went ahead and took it out started looking for old batteries and found some. I read the manual and said lets try it. It is simple fast and efficient you set the time for current the amount of current. Push up on the two rods with battery and sparks for a micro second and bam soldered as you see the spot welds in his picture. Not bad I must say for the money I am still scratching my head as I didn't expect it to be so easy. If you like pm me an email and I can video it for you. Or maybe I should put here on this thread in case others that might want to tackle making there own pack. If its ok with everyone I can post it here.

 

[bonald]

Yes, post it here, we need some pics of that spot welder!

 

[trevc2]

Also curious which model you went with. Are the welds strong, have you tested them by trying to pry apart with your hands?

 

[Ebikebert]

Yes, post the pics of the welder here if you want to. That is a good price for a spot welder i am curious as well to see if it is difficult to pull it apart with your hands. I made a tab welder once out of car audio capacitors but never got it good enough to make it leave tab material on the batteries. If the welder is capable of leaving tab material on the battery weld after prying it off I would definantly say forget about making your own and just buy the one you mentioned. Tell us if it leaves tab material on the battery after prying that is the best test. :wink:

 

[ecruz]

Yes I tried to pull it apart and its not coming off. Its bonded well It will probably rip the spotweld clean with piece of battery. When I get a chance I will set up camera do a weld and rip with pliers or something for you guys. I just didn't want to barge on your thread but since you are all curious by all means. Here is a picture of the unit.

 

[trevc2]

Yes I tried to pull it apart and its not coming off. Its bonded well It will probably rip the spotweld clean with piece of battery. When I get a chance I will set up camera do a weld and rip with pliers or something for you guys. I just didn't want to barge on your thread but since you are all curious by all means. Here is a picture of the unit.

Apparently one downside to those models is that the tips wear down after 60-100 welds (according to some of the manufacturers). I wonder if we can find higher quality tips? (like Tungsten, etc).
For Australian members, that spot welder model is going for $145 shipped on Ebay from China.

 

[parabellum]

Nice. Good weld usually looks like that.

 

[ecruz]

Yup that is what the weld looks like. I will try to put on video when I am home and can do the setup. It came with 3 set of tips but frankly the tips just look like copper bars really small you just file them to keep them clean with a nail file and I don't see why they wouldn't last a whole pack. I guess as I get to play with it more we will see. But I am pretty sure it will last my build with no problem.

 

[Ebikebert]

wow that is great if it is capable of leaving material behind. I am definantly going to give this welder a second thought for my next battery pack.

 

[sflorlando]

Ive been looking for a decent welder for quite some time. It seems like there are two options the very cheap junk or the super expensive commercial variety. Hope this fits the bill. I did see that Dogati used one for his build. http://endless-sphere.com/forums/viewtopic.php?f=3&t=51612 seems he had a few problems with blowing fuses and triacs.

 

[ridethelightning]

those little welders look really handy.

whats the general consensus on them, apart from the tips burning out, do they last ok?