What's the current gamut of solderless/weldless 18650 battery pack construction?

Barncat

1 kW
Joined
Oct 26, 2020
Messages
359
Just asking those who've been around this field for a while... All I'm really aware of is the Vruzend system.

I've just built what I believe to be a novel enclosed prototype that's efficient, quick and easy to assemble/disassemble, with all copper buss bars and low part count.
 
Not willing to post pics at this time... Ordinarily i would for a regular build thread. The US patent process changed some years ago from first to "reduce to practice" to first to file. I've been an inventor for decades.

I did start scanning the "sticky" post in this category an hour ago re no-weld stuff. The part I built was arrived at independently before looking at any of that but I've not researched all the "prior art" yet. There are some similarities, as there are only so many ways to repackage these cells.

I suppose my query is for those of you who eat sleep and breathe this topic as to whether there are any/many commercial "drop in" pack cases out there. Web search doesn't always find everything.
 
No idea what you mean by "commercial drop-in cases". You'd have to post pics of what you are talking about.

If you're trying to judge whether you have a product that you could sell, then you can do your own research on that stuff--there's many years of posts of people's personal systems and commercial builds, in both build and troubleshooting threads, if you need data it's out there--you just have to spend the (huge amount of) time to read it all. :) No reason for anyone else to help you make money if they don't get any of it. ;)

Keep in mind that this forum is really a DIY forum for open-source development of ideas. Most people here that make things post about them here so others can use those ideas.

Also remember that as far as all this stuff goes, patents are essentially useless--it will be somewhere in Asia that copies whatever you come up with. You wont' even have to post it yourself--as soon as you sell it and someone over there buys one, if it's cheap and easy to make they'll copy it and others will copy that, and they'll be able to do it cheaper than you can. Or if you have someone over there make them for you, they'll also make them for themselves, to sell, or for others to sell, etc.
 
In my experience, if it's easy to make it's easy to break :lol:
 
I have 3 kits, NESE, VRUZEND, AND THAT GOOF WITH THE MAGNETS.

VRUZEND work well, especially the latest release. NESE are nice too. I have a 7s3p Vruzend original that has worked well from day one.

Pictured before BMS. (Clear cell sleeves)
 

Attachments

  • 4ADDB10D-1501-4C06-8D28-2E671A4DBEEF.jpeg
    4ADDB10D-1501-4C06-8D28-2E671A4DBEEF.jpeg
    61.7 KB · Views: 1,773
  • 12409801-D48B-471D-A1FA-10E15BCEADB6.jpeg
    12409801-D48B-471D-A1FA-10E15BCEADB6.jpeg
    54.4 KB · Views: 1,773
tomjasz said:
I have 3 kits, NESE, VRUZEND, AND THAT GOOF WITH THE MAGNETS.

VRUZEND work well, especially the latest release. NESE are nice too. I have a 7s3p Vruzend original that has worked well from day one.

Pictured before BMS. (Clear cell sleeves)
I dont think i saw your NESE pack built. If i can remember correctly, you were going for the hardware and were printing modules locally? Have any photos remaining?
 
Thanks all for the input. Wasn't asking anyone to do a lot of research- just a sentence or two about what's out there.

In the past 24 hours I believe I've scanned most of the archived material on this topic here on the forum. Obviously there are dozens of considerations when assessing the novelty, marketability and liability of a new product. Not my first rodeo as they say, though I'm new to the forum.

After further testing I'll determine feasability, but yes, these days anything that's a better mousetrap would be immediately copied overseas. Even a provisional patent is a lot of work. And liability is a pretty big negative with this one.

So the jury is out but I may just post pics eventually.
 
I built my 13S/5P Battery using 18650 Pansonic 3,400ma cells last year.
Over the Christmas break I converted it up to a 14S/6P using the same type of cells and a 14S Daly BMS
I think the solderless Vruzend has advantages and Dis-advatages.
To be able to dismantle easily etc is all good.
However I have had problems with the cells not conducting through the top caps. You will note in my second picture that I have installed extra through bolts with washers . This gives extra force to keep the whole battery together.
I like the system and it works well on my E-Bike
Bill C
 

Attachments

  • 14S-6P Battery 008.JPG
    14S-6P Battery 008.JPG
    358.2 KB · Views: 1,663
  • 14S-6P Battery 009.JPG
    14S-6P Battery 009.JPG
    407.5 KB · Views: 1,663
Hey SirW- thanks for relating your experience. The Vruzend system obviously works. The part count is astronomical however.

Looks like that and the NESE are about it other than some DIY experiments.

There are a lot of compromises with battery selection and construction- particularly for such lightweight vehicles as bikes and stand up scooters etc...
 
agniusm said:
tomjasz said:
I have 3 kits, NESE, VRUZEND, AND THAT GOOF WITH THE MAGNETS.

VRUZEND work well, especially the latest release. NESE are nice too. I have a 7s3p Vruzend original that has worked well from day one.

Pictured before BMS. (Clear cell sleeves)
I dont think i saw your NESE pack built. If i can remember correctly, you were going for the hardware and were printing modules locally? Have any photos remaining?

Health issues arrested the printer build. I just ordered another set. Complete with cases. I used the cases I had for a solar light. Sadly it’s buried in the build and I never took pictures. A couple of years from now I’ll take it apart to replace batteries.
 
Barncat said:
Just asking those who've been around this field for a while... All I'm really aware of is the Vruzend system.

I've just built what I believe to be a novel enclosed prototype that's efficient, quick and easy to assemble/disassemble, with all copper buss bars and low part count.
Appreciate the convenience of the VRUZEND V2.1 thirty cell kit as a first DIY 10s3p build (reasonably priced) and disassembly convenience for experimental testing. The major drawback is it's stainless steel spring contact cap inserts that negate the advantage of the NI/CU bus bars and only 8 barrel bolts instead of 16.

My pickiest concern is that the V2.1 doesn't use red cathode caps and black anode caps. Micah had decided to use red and blue caps for the V.16 kit which is no longer his best seller having both stainless steel contact cap inserts and stainless steel bus bars. So, he decided to use orange and black caps for the V2.1 kit with its NI plated CU bus bars. Being a stickler for detail i'm considering ordering a V.16 kit and paint the blue anode caps black plus more barrel bolts for the V2.1 kit.

Micah's original suggestion of using a hammer was almost laughable. I removed the pink wrap from my 30Q cells for an easier fit (and ease of removable) with addition of an extra adhesive insulator ring/washer on cathode end. That way the cells are easier to remove and imo all 16 barrels bolts should be used instead of just 8 that come with the V2.1 kit. Thus a reason for buying the less expensive V.16 kit with more parts so you'll have extra caps for experimenting and enough barrel bolts for assembling a V2.1 kit for a secure fit.

I've made some copper contact cap inserts and am currently doing 4-wire IR comparison tests as well as tracking the self-discharge of the Samsung 30Q 141 cells since 1/2/21 when all thirty were charged to 3.75v. Three of the 30 suffer from what i'd call high self-discharge and another 5-6 from moderate self-discharge. Will be replacing them with good 30Q cells this coming February. I've only drawn the battery pack down as low as 32v (3.2v/cell) just three times as that's the voltage cut-off of the 20 amp Controller. My 10S3P 30Q 141 V2.1 has 170 charge/discharge cycles with the majority of them from 4.1v to 3.5v-3.4v with average amperage draw about 7 amps.
 
Well... stainless is of course on the bottom end of the conductivity scale, but at least it doesn't corrode...

Your attention to detail will help improve the breed eMark.
 
Barncat said:
Well... stainless is of course on the bottom end of the conductivity scale, but at least it doesn't corrode...
The real QUESTION: Is the VRUZEND V2.1 kit good enough as is for its niche market application?
tomjasz said:
VRUZEND work well, especially the latest release [V2.1 kit]. I have a 7s3p Vruzend original [V1.6 kit] that has worked well from day one.
For my conservative etriking the V1.6 kit would've served me just as well as going with the V2.1 kit. As far as "raw performance" (voltage sag) it's the least of my concerns. Average pull from my 10S3P 30Q is 4-7 amps 60% of the time, 8-10 amps 35% of the time and above that only 5% of the time when going up a grade for 15-30 seconds pulling as much as 19 amps from my 20 amp controller with a 750w front drive motor.

The photo of the red cap on the left using 10g copper and a nickel-plated copper bus bar has a resistance of 7-8mΩ measured from inside the cap to the upper end of the bus bar shown at the top of the photo. Was satisfied that the M4 0.70 threaded 10g was sufficient although I wouldn't recommend it to anyone else as the threads can be stripped by over tightening. The red cap on the right with the ss compression insert and also with nickel-plated copper bus bar has a resistance of 18-20mΩ with same measurements. Thus the noticeable difference between copper (or even aluminum) and stainless steel. Used an AideTek SM8124A (4-wire) for the readings ... the photo tag line is wrong as it should read "Both With Nickel-plated Copper Bus Bars"

My copper bus bar experiment was made from 3/8" copper anodized tubing; however by the time I flattened it using a heavy duty machinist vice any anodizing to prevent corrosion was vastly diminished as you can see from the photo.

Bottomline: The VRUZEND V2.1 kit fills a niche market especially as a relatively inexpensive beginner DIY build. IMO, Micah is worthy of an innovative ingenious merit award for his VRUZEND kits. That said it's also understandable why some of the spot-welding (raw performance) braintrust at ES may consider the VRUZEND kits to be "crap".
 
Your performance requirements are pretty conservative eMark, but you have some data there re copper vs stainless. Those kits have their purpose and it's not my place to critique them.

I'm coming at this from a mechanical engineer's perspective. I should have more to report on my project in a week or two.
 
Barncat said:
I'm coming at this from a mechanical engineer's perspective. I should have more to report on my project in a week or two.
Being VRUZEND V1.6 or V2.1 (for the price) may be your primary competition here's some more mechanical/electrical consideration as electrical IR is relative to your mechanical design. You are most likely already familiar with the following, but decided to post anyway for other interested VRUZEND DIYer's ...

The threaded ss stud (IMO) should be a larger M4 0.70 metric stud for a couple reasons as it's easier to start the nut with your fingers. Also the VRUZEND precision bus bar holes (on center) in both the V1.6 and V2.1 bus bars will readily accept a M4 0,70 threaded stud which IMO is a better tight fit mechanically and electrically than the current smaller threaded studs. The bus bar holes are precision drilled center hole to center hole for DIY assembly using M4 0.70 threaded studs.

The reason Micah used a hammer and/or woodworking clamps was to make sure the stainless steel cap inserts were completely compressed against the head of the threaded stud. With the later addition of barrel bolts in the kits insured a secure fit with the ss insert remainig fully compressed. Here's the difference in mΩ readings with the ss compression inserts being partially compression and fully compressed with the mΩ reading taken at the adjoining hole connection of the bus bar ...

11.5mΩ ~ not fully compressed with mΩ reading taken at outer hole of ss bus bar
10.3mΩ ~ fully compressed with mΩ reading taken at outer hole of ss bus bar

8.2mΩ ~ not fully compressed with mΩ reading taken at outer hole of ni/cu bus bar
7.0mΩ ~ fully compressed with mΩ reading taken at outer hole of ni/cu bus bar

4.5mΩ between ss bus bar holes
2.2mΩ between ni/cu bus bar holes
2.3mΩ + 0.7mΩ + 0.3mΩ = 3.3mΩ (e.g. 8.2mΩ to 11.5mΩ in above comparison)

For each 18650 cell double the above mΩ's being two VRUZEND caps on each cell (cathode end and can anode end) of an 18650 cell.

With the above mΩ readings one could figure the total mΩ IR of a VRUZEND battery pack kit IF so inclined figuring all the series and parallel bus bar connections whether ss or ni/cu bus bars.

The attached photo shows how i took the mΩ readings of the ss insert partially compressed and fully compressed (difference of 0.7mΩ). There was an additional 0.3mΩ's when taking the readings of the ss insert with bus bar attached to the cap which is represented in the above comparisons. IMO if a larger threaded screw (M4 0.70) were used it would be a better fit all around and possibly negating the additional 0.3mΩs in the above comparisons.

Bottomline: When the VRUZEND ss insert (V1.6 or V2.1) is fully compressed the mΩ reading between the cell cathode fully compressed contact and threaded stud bus bar contact is only 1.3mΩ (at most) ... so we shouldn't be overly concerned about the compression cap insert being stainless steel when fully compressed.
 
EMark- you've spent some time on studying all those fasteners... I'm getting closer to real world on-bike testing of my idea. Works fine on the bench, but anything does. One big potential upside is very few fasteners.

The first layout I built was 10s7p. I decided that two of those are just too large- at least for the bmx frame build I'm doing. So I'm going with a single 20s5p.

I have (2) 36V 35A bms. Is it possible to wire and charge the pack as 72V, or must I wire in series and charge independent 36V packs? I was unable to find that answer by search. Any of you guys would know...
 
Barncat said:
I have (2) 36V 35A bms. Is it possible to wire and charge the pack as 72V, or must I wire in series and charge independent 36V packs? I was unable to find that answer by search. Any of you guys would know...
You could wire the two 36V 10s packs in parallel when charging with a 36V charger. Then rewire the two equally charged 36V packs in series as a 72V pack. Get one good "smart" 72v BMS, if your two 36V BMSs are on the cheap side.

It would be nice to have a 72V charger ... https://www.amazon.com/Charger-Li-ion-Battery-Aluminum-3P-Plug/dp/B07R33QHD4/ref=sr_1_3?dchild=1&keywords=72+volt+battery&qid=1611005083&sr=8-3 ... prefer Amazon instead of a less expensive Ali product even at half the cost. If defective or problem Amazon is good about refund or ordering another that works, or if not return again and try another brand.
 
Thanks for the suggestions and link. Decent looking charger. I need to do a bit more bms study...
 
eMark said:
It would be nice to have a 72V charger ... https://www.amazon.com/Charger-Li-ion-Battery-Aluminum-3P-Plug/dp/B07R33QHD4/ref=sr_1_3?dchild=1&keywords=72+volt+battery&qid=1611005083&sr=8-3 ... prefer Amazon instead of a less expensive Ali product even at half the cost. If defective or problem Amazon is good about refund or ordering another that works, or if not return again and try another brand.

I use this one. It's like the Swiss Army knife of chargers. Even charges my motorcycle battery. Fully programmable. I think it's also actually made in North America! It is a little pricy though.

https://www.amazon.com/Satiator-Programmable-Electric-Battery-Charger/dp/B01LWT3UH0
 
Grin (Justin) is Canadian, great outfit!

He designed and spec'd but of course it's actually manufactured in China, or Asia at least, would be 10x more expensive do make anywhere else.

Great product line, three different models, get the lowest voltage version that suits your need in order to get higher amps.
 
Back
Top