DIY assembly kit for 18650 without spot welding/Soldering

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spinningmagnets   100 GW

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by spinningmagnets » Oct 07 2017 9:11pm

I bought two boxes of Vruzend 18650 end-caps in order to be able to write an article about them (wonderful product, BTW). If you bought a box, and need just a handful more to complete your project...I will sell what I have at cost...send me a PM.

Located in Kansas 66441. (what I mean is, I will not make any profit, I will sell one cap, two caps, ten caps, twenty, etc...)

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by nathan89 » Oct 08 2017 2:39pm

They're available from nkon now it seems.

https://eu.nkon.nl/vruzend-diy-battery-kit.html

Might be better for some people, depending what country you're from :)

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by Microbatman » Oct 14 2017 9:49pm

I ordered the new kit with red and blue caps

It is great!!!

I would like to find a way to
Replace the small bus bars for 1 long continuous bus bar.
1 bar = cleaner build with less breaks in the connections.

Building a 28s10p battery. It will be subdivided into Four 7s10p

Considering copper or nickel or tin plated copper strip.

So rather than connecting 5 bars together for a parallel run you only connect 1 bar to eliminate breaks.

Right now the plan is to use the supplied bus bars in the kit and supplement it with a continuous nickel strip that is available through Vruzend.

But I am also considering the copper or nickel plated copper buss bar idea.

Anyone know where I can find copper bus bars?
Anyone know where I can find tin plated copper bus bars material?

Would having 1 continuous bus bar on each parallel row make that much of a difference reducing resistance?
I will be pulling max 4000 watts of power from my 28s10p battery. And continuous between 1500 to 2000 watts.
MotorCrystalyte X5304 20 Inch Rear Wheel DISC Brake Controller Crystalyte 48A72V4110MOSFETS
Batteries A123 24s2p
Charger Mastech 5020
Frame Azonic Steelhead
Grateful/fortunate/blessed to have the resources and family support to enjoy my ebike hobby

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Matador   10 kW

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by Matador » Oct 15 2017 10:31am

Just a little reminder.
Epoxy glue is not a good choice for bonding "low-energy plastics" like polypropylene plastic.
Polypropylene is way too chemicaly stable to be bound reliably with epoxy glue...
Try glueing tupperware with epoxy for a test, you'll see the glue will pop right off with very low force needed to unstick it.

Matador

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by riba2233 » Oct 15 2017 11:22am

Matador wrote:Just a little reminder.
Epoxy glue is not a good choice for bonding "low-energy plastics" like polypropylene plastic.
Polypropylene is way too chemicaly stable to be bound reliably with epoxy glue...
Try glueing tupperware with epoxy for a test, you'll see the glue will pop right off with very low force needed to unstick it.

Matador

How about ABS or PC? Thanks!
Last edited by riba2233 on Oct 15 2017 12:12pm, edited 1 time in total.

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by spinningmagnets » Oct 15 2017 11:39am

Anyone know where I can find copper bus bars?
I recommend that you first make sure that you are certain about which thickness of copper you want to use. Then? order copper sheet and cut it yourself. If the copper sheet is 0.25mm or thinner, then you can cut it with common scissors. If it is thicker, then you might purchase some sheet-metal shears (which look like heavy duty scissors with short blades).

If you don't own a cordless drill, I recommend buying a Dremel, since it is much more useful for a variety of tasks that are light-duty (drilling small diameter holes, plus operating an abrasive disc for cutting metal). Dremels can accept drill bits in the small sizes, but check first before you spend money. You might check thrift shops for a used drill or Dremel at 75% of the price of a new unit.

round part 16mm dia (8mm to center). Total length 50mm, center of disc to center of first cutout 22mm, then 35mm, strip is 8mm wide.

0.25mm .010 inch

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Matador   10 kW

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by Matador » Oct 15 2017 11:51am

riba2233 wrote:
Matador wrote:Just a little reminder.
Epoxy glue is not a good choice for bonding "low-energy plastics" like polypropylene plastic.
Polypropylene is way too chemicaly stable to be bound reliably with epoxy glue...
Try glueing tupperware with epoxy for a test, you'll see the glue will pop right off with very low force needed to unstick it.

Matador

How about ABS or PC? Thanks!
ABS can lightly sanded and glued with some inexpensive glue. Epoxy might work with ABS, I`d do some research on google.
I don`t know about polycarbonate, but my guess is epoxy will not form a good atrong bond (I think polycarbonbate is another one of these "low surface energy" plastic). I'd try googling it.
I have experience with Polyacrylate (Perspex aka plexiglass)... And that will not work with epoxy either.

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by riba2233 » Oct 15 2017 12:11pm

Great, thank you! I have glued magnet that comes with CA to the half-shaft on my car with metal epoxy, sanded one side of it's plastic casing before, and it's also being held by magnetic force. I hope it will hold lol :lol:

Sorry for OT!

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by mlt34 » Oct 18 2017 9:36am

Microbatman wrote:
Would having 1 continuous bus bar on each parallel row make that much of a difference reducing resistance?
The parallel connections between the 10 cells actually has very little current flow, we're talking on the milliamp scale. All of the current that is part of the 'power' your motor and controller is drawing will pass through the series connections. The parallel connections only see small balance current. So copper that you're talking about for the parallel connections won't have as much effect on resistance as if you did it for the series connections.

If you're in the US then I've bought copper strips from BasicCopper.com. Since they are strips of 1" wide, you can usually just cut it in half or thirds to make bus bars, and the cost is nearly the same as buying a sheet (sometimes cheaper depending on the sheet size because the copper strip roll and can ship for cheap).
Are you planning your first electric bicycle conversion? I wrote a book that teaches beginners everything they need to know about building their own ebike.
Then I wrote the book (literally) on building custom lithium batteries.
I also write for EbikeSchool.com, a site that does mainly how-to style articles and other informational write-ups. Check out our youtube channel for great how-to battery building videos.
Lastly, I run www.Vruzend.com, which sells solderless 18650 battery kits, 18650 cells, li-ion chargers, BMSs and more!

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by nathan89 » Oct 18 2017 1:13pm

Just checking the caps that arrived today and seems too much force has been used when inserting the bolts through the holes and the plastic has cracked.

edit. Roughly 50% of red caps are damaged in the same way. If you look at the one on the right in the image you can see the bolt isn't central which is possibly what's caused the issue.

Very poor quality control it seems.

edit #4. Vruzend replied to my email and said they're okay, just build a pack and be happy.

Maybe 25% have been assembled properly, the rest either have stress marks or have small cracks. Why would I risk building a pack with these? What happens if the cracks get worse while riding my bike..
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mlt34   100 kW

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by mlt34 » Oct 19 2017 8:03am

Hey Nathan,

Micah here from Vruzend USA. I haven't read your email exchanges so forgive me if I don't have all the details, but perhaps I can shed some light here.

I totally understand what you mean. You buy something new, open the box, and then its like "hey man, there's a crack right here". You're not wrong.

In this case though, this little crack at the threaded terminal is actually just a superficial artifact from the production process. It's even visible in product photos, along with other small imperfections like occasional flashing from the mold that also doesn't affect performance. That spot right at the threaded terminal isn't actually a load bearing spot - all the force from the spring tension is transferred to the rim of the cap, not the center. The threaded post itself performs the electrical connection, but not the physical connection. The joining force comes from the interlocking on the sides of the cells. So while you're absolutely right and there is indeed a small crack there, I can tell you that it has absolutely no impact on performance. In fact, when you tighten down the bus bar, you're effectively creating a mending plate to support the plastic between the busbar and the internal portion of the spring contact, further strengthening that section.

I was responsible for a lot of the testing of this system, and I specifically worked with caps that looked like these to ensure this wasn't a performance issue over time. Even so, we're constantly working on improvements. We've reinvested in better machinery and tooling to make sure these little manufacturing imperfections are minimized and ultimately eliminated. Plus we've got some other things in the pipe that its too soon to give much detail on, but we're actively working to make a good product even better. I'm confident that you'll build a great battery from your Vruzend kit, and I'm happy to help if you need any assistance or have questions along the way. You can shoot me a PM here or find my email address on the ebikeschool.com youtube page.
Are you planning your first electric bicycle conversion? I wrote a book that teaches beginners everything they need to know about building their own ebike.
Then I wrote the book (literally) on building custom lithium batteries.
I also write for EbikeSchool.com, a site that does mainly how-to style articles and other informational write-ups. Check out our youtube channel for great how-to battery building videos.
Lastly, I run www.Vruzend.com, which sells solderless 18650 battery kits, 18650 cells, li-ion chargers, BMSs and more!

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by nathan89 » Oct 28 2017 10:03am

Thanks for your reply but I really think I'll try open a case with paypal and see what they think, as they don't seem fit for purpose. The clear ones looked much better quality in your videos..

*edit* added another photo. I actually saw similar damage in one your videos. Just concerns me that it's going to be hard to insert the cells when the outer area is already cracked on some of them? Hate to be negative but no other option :/

*edit2* used my old phone to take better photo to illustrate the poor quality of the mould. I know they're "cheap" but should we really accept this?
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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by Jil » Oct 29 2017 5:48am

mlt34 wrote:
Nice tutorial, thanks !

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by spinningmagnets » Oct 29 2017 7:59am

I'm not saying this is a good idea, but...I'm just saying this might work. Take a razor-knife or a Dremel and cut a slot in the plastic cap for a copper ribbon to pass from the inside to the outside...0.25mm thick copper overlay, cut with scissors...
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3...add a self adhesive insulation washer to the positive ends...
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Dimensions:

Round part is 16mm dia (8mm from edge to center). Total length 50mm, center of disc to center of first cutout 22mm, then 35mm, strip is 8mm wide.

0.25mm, 0.010 inch thick, I would shave the 18650 wrapper at the bottom / negative electrode, so there would be good contact. Of course, the self-adhesive insulation-ring / washer is only for the positive tip. 8mm X 0.25mm is equal in cross-section to 14-ga copper wire.

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by Matador » Oct 29 2017 11:08am

Nice one SM !

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by Jil » Oct 29 2017 1:53pm

Hi !
Quick question for the persons having made a battery pack with the Vruzend kit :
I would like to build a Vruzend 10S 6P pack (ie. 60 18650 batteries), to install it under my top tube. But I need to know the exact size of the kit assembled, because it's a matter of cms that it will fit (or not) to my bike.
I know that the dimensions of a single Vruzend cell are 22*22*88mm, but when assembled the overall dimension is not exactlly the same, slightly smaller.

Could you tell me what would be the exact dimensions of a kit with 3 cells in width and 20 in lenght ? It's mainly the lenght of the pack that could be a problem. If it's less than 42cm it's OK, if it's more I will have to go for a 50 cells battery instead of 60.
Or alternatively, could you indicate me the type and dimensions of your pack, so than I can extrapolate ?

Many thanks :)

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by optimistx » Oct 30 2017 5:19am

nathan89 wrote:Thanks for your reply but I really think I'll try open a case with paypal and see what they think, as they don't seem fit for purpose. The clear ones looked much better quality in your videos..

*edit* added another photo. I actually saw similar damage in one your videos. Just concerns me that it's going to be hard to insert the cells when the outer area is already cracked on some of them? Hate to be negative but no other option :/

*edit2* used my old phone to take better photo to illustrate the poor quality of the mould. I know they're "cheap" but should we really accept this?
I got one set of Vruzend kit from India.

There were several unexpected things:

1. The nuts could not be tightened due to the bolts rotating freely. Initially I found 22 items with this defecft, but later more.
2. When the assembly is completed but one bolt in the middle starts rotating, I have to disassemble almost all items! The fishtails are such that even in a set of 10 adjacent items I have to to separate all items 1, 2, 3, 4, 5, 6, 7, 8 to replace defective item 9 ! (if there is a better way I would be curious to know it).
3. Some of the plastic parts have cracks and the center holes for bolts are irregular
4. When attaching balance wires to the bolt, under the nickel strip as instructed in ebikeschool videos, the wires can sink into the plastic creating a very unsecure contact .
5. When reporting to India about 22 defective items, I get a proposal that they might send 22 new items. Not even an apology. That might be legally correct procedure. But if NASA gets a new screw from India after having lost a satellite due to its defect, is NASA happy with the outcome? I am not NASA, but anyhow, you might understand....

I have not filed a complaint to Paypal, and have not accepted the 22 item proposal.

I initially often encourage new ideas and new startups instead of established solutions and companies. But this time I start to hesitate, if that is worth it.

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by nathan89 » Oct 30 2017 8:34am

The solution to the problems both of us experienced is simple - to slow down production. I would've happily waited an extra week if it meant all caps were assembled correctly. Also I'd not looked at the rest of the kit until now and I see that all bus bars are bent on one end :roll: :lol:

I wonder if you had any problems since completing your battery? I don't want to build a pack and then have problems in a few months as this is going to be on a bike for commuting to work.

*update* Vruzend told me to just assemble a small pack and be happy, so i did. and all i can say is LOL. Used clamps like Micah showed in his videos and this is the end result. 2 red caps cracked. I'd read the gap between the cap when fully compressed should be 44mm, and mine are around 45/46mm.
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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by mlt34 » Oct 31 2017 2:43am

nathan89 wrote:
*update* Vruzend told me to just assemble a small pack and be happy, so i did. and all i can say is LOL.
Alright Nathan, now this bothers me. You are simply being dishonest. This is not at all what Urvakhsha said to you. He is an exceedingly polite guy, even more so when you consider that English is not even his first language. He and I were both shocked that you would so grossly misrepresent his words, so he sent me the email to see for myself. Here it is:

Image

He most certainly did not tell you to "build a small pack and be happy". What he asked of you was to simply test the caps to see if they worked, perhaps by first building a small pack, and if you found the caps to not work then he would either refund your money completely or send you an entirely new replacement kit, free of charge.

You were offered a complete refund or replacement of your caps in a very polite email, but you conveniently left all of those details out of your post because they didn't fit your narrative.

I'm a pretty chill guy, but it riles me up that you would go out of your way to put words in Urvakhsha's mouth and publicly lambast him when all he did was politely offer to solve the problem and make things right for you.

Ok, now optimistix
optimistx wrote:When reporting to India about 22 defective items, I get a proposal that they might send 22 new items. Not even an apology. That might be legally correct procedure. But if NASA gets a new screw from India after having lost a satellite due to its defect, is NASA happy with the outcome? I am not NASA, but anyhow, you might understand....

I have not filed a complaint to Paypal, and have not accepted the 22 item proposal.

I initially often encourage new ideas and new startups instead of established solutions and companies. But this time I start to hesitate, if that is worth it.
Here again, I don't think this is a fair representation of what you were told by the Vruzend team. Urvakhsha sent me this email exchange as well:

Image

You were not told that we "might send 22 new caps", you were told that we would be happy to send them to you for free, or to refund the 22 caps (whichever was more convenient for you) and that if you ever placed another order with us, we would include extra items to make up for the problem you experienced. In this case, you were unsatisfied (which is of course totally understandable) and so you were offered a complete refund or replacement. You're right that the email didn't specifically use the word "sorry", but it was exceedingly polite, you were thanked multiple times for your understanding, and you were offered as much further assistance as you needed. Yes, if I had written this email myself I would have included the word "sorry" but again, this is not his first language and the tone of the email is very polite as he is going out of his way to offer many different solutions to make this right for you.

As everyone knows, we are a new and small operation. We have been inundated by demand and have been trying to grow fast enough to meet that demand. In this case, our QC didn't catch some of these caps but we have made production and process changes to solve these issues. We don't hide the fact that we have erred, but we always stand behind our product. We have taken the feedback from these above cases to heart with solid changes to our process. We have just upgraded the machinery on our production line and are close to finishing a new mold for the caps that will further improve the design and solve the issue that these two gentlemen experienced. We certainly appreciate this feedback because it helps us to make these improvements. As we continue to grow, our goal is to continuing improving. And we will always stand behind our products, as we have done so since the beginning.
Are you planning your first electric bicycle conversion? I wrote a book that teaches beginners everything they need to know about building their own ebike.
Then I wrote the book (literally) on building custom lithium batteries.
I also write for EbikeSchool.com, a site that does mainly how-to style articles and other informational write-ups. Check out our youtube channel for great how-to battery building videos.
Lastly, I run www.Vruzend.com, which sells solderless 18650 battery kits, 18650 cells, li-ion chargers, BMSs and more!

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by Jil » Oct 31 2017 3:59am

mlt34 wrote: As everyone knows, we are a new and small operation. We have been inundated by demand and have been trying to grow fast enough to meet that demand. In this case, our QC didn't catch some of these caps but we have made production and process changes to solve these issues. We don't hide the fact that we have erred, but we always stand behind our product. We have taken the feedback from these above cases to heart with solid changes to our process. We have just upgraded the machinery on our production line and are close to finishing a new mold for the caps that will further improve the design and solve the issue that these two gentlemen experienced. We certainly appreciate this feedback because it helps us to make these improvements. As we continue to grow, our goal is to continuing improving. And we will always stand behind our products, as we have done so since the beginning.
It's normal to encounter some production issues when bringing a new product to market.
I'm gratefull that people like the Vruzend's team invent smart products to make our life easier :D

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by nathan89 » Oct 31 2017 6:51am

I first contacted Vruzend on the 18th showing the damage around the bolt and was offered no refund or replacement. Told to build a pack to test and they'll be okay.

On 19th I sent another message about being sceptical of building a pack as I was wary the cracks may get worse. "Make a pack. You wouldn't be disappointed." Was part of the response I got, which is why I said "build a pack and be happy" I don't think those words are grossly misrepresenting what I was told?

On 28th I sent another email illustrating the damage to the side of the cap. Which I pointed out is also visible in one of your videos, and I told him the quality wasn't acceptable and I was tempted to open a dispute with Paypal.

30th I get the reply "You have my word sir, go ahead and make a pack. If it doesnt work out you will get a full replacement or refund"

I then reluctantly attempt to put 4 cells together and they cracked.

After I email him, he say I'll get a replacement which are much better quality.

You're right that I didn't show the full conversion but maybe you should understand how frustrated I was. I never said anything bad about either of you guys. My only criticism was that they should produce them in a lower quantity to ensure quality is high.

I'd be interested to know what my narrative is? To attempt to discredit Vruzend or what? I certainly haven't gained anything by spending $45 on a product I can't use and now have to wait 3-4 weeks to get a replacement.

I certainly wasn't dishonest and don't appreciate public attacks against me - Thanks :)

*edited multiple times*

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by Matador » Nov 01 2017 12:00am

Jil wrote:
mlt34 wrote: As everyone knows, we are a new and small operation. We have been inundated by demand and have been trying to grow fast enough to meet that demand. In this case, our QC didn't catch some of these caps but we have made production and process changes to solve these issues. We don't hide the fact that we have erred, but we always stand behind our product. We have taken the feedback from these above cases to heart with solid changes to our process. We have just upgraded the machinery on our production line and are close to finishing a new mold for the caps that will further improve the design and solve the issue that these two gentlemen experienced. We certainly appreciate this feedback because it helps us to make these improvements. As we continue to grow, our goal is to continuing improving. And we will always stand behind our products, as we have done so since the beginning.
It's normal to encounter some production issues when bringing a new product to market.
I'm gratefull that people like the Vruzend's team invent smart products to make our life easier :D
Same here ! Vruzend is absolutely absolutely awesome. I`m gratefull they invented such a great product.
And despite some small talk about issues of the product not being absolutely perfect and not being up to NASA specification and all, I will continue to support them in the future.

They are the firsts one who actually produced what I had been looking for years but could not find anywhere,
There's only very few poeple on this planet who actually create new stuff, innovate.
Vruzend is one of them.
Plus, their custumer service is number one. From my numerous exchanges with Urshakhva, I know that he has put all is heart into designing this product, with the intent that himself would also use it.
What more can I ask... NASA-speced products for the price chinese produced cell holders that don`t even have contacts or bolts ? Dream on :roll:


PS : Vruzend have the best model. Start with a product that everyone can afford. It might not be totally perfect right off the bat, but at least it exists and is available... Since it`s affordable, Vruzend is rewarded with capital/funding, and then, the product gets to evolve and get perfected... through costly reseach and developpement.

Nobody would buy a 100 piece kit for 20000$ even if it`s perfect right off the bat because they spent years and yeats doing research on it before even selling one... Nobody, maybe except the NASA. I`m not the NASA.The best way to perfect a product made for the mass market is to experiment it through the mass market and see if they like it.
Most people that tried this kit are very satisfied with it !

Anyways... Easy to criticise others. I just wanna say THANK YOU for coming up with such a great product and innovation VRUZEND.
If I had a bit of time in this extremly busy time of my life, I would take pleasure to join your team and help the devloppment of this awesome product! The Vruzend solution deserve strong attraction !
Matador
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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by spinningmagnets » Nov 01 2017 12:09am

I found the price to be quite reasonable. If I were building a pack with these I would order a few extra, because I expect a few flaws at these prices. The stock contacts are fine for the huge demand that is growing for a DIY "Tesla power wall", for which there are many youtube videos to provide the details.

If you want to use 10A per cell, I experimented with adding copper over the steel (see pics above), and I think that would work fine.

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by optimistx » Nov 01 2017 9:19am

mlt34 wrote: ... and so you were offered a complete refund or replacement.
...
complete? The kit was 21 USD and mailing 19 USD. Do you mean these costs would be refunded or a complete new good set sent? What about the cost of mailing the whole kit back to India ( if required) ?

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Re: DIY assembly kit for 18650 without spot welding/Solderin

Post by Tats » Nov 01 2017 5:07pm

Personally I think the kit is way under-priced for the functionality it provides. All those bits and bobs and shipping for less than 50 bucks?

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