Recyclable Lithium Box, lets you build batteries in 15 minutes. Crowdfunding technology

Pre launch video for a new technology via crowdfunding

Hi everybody, I am a big fan of powerwalls and home arrays of lithium. Do you think it will be OK if I post this technology to the discussions forums? Please sign up on the project home page if you want to watch the launch day as it happens, as soon as I have enough subscribers www.batgroupcraft.com Please Sign Up!

here is a technology so that people will be able to 3D print templates for free boxes and use super high quality materials like FR4 to save lots of time building home lithium banks. I'm still working on the video, have to add some BMS illustrations.

I don't hate the idea, would be great for beginners to learn with. Personally, I dislike the springs but time will tell if this idea will match up to all the other similar ideas.

Hey HBPowerwall! thanks for the point of view! I have been building batteries since 2003 and hitting them with rocky roads, letting them fall sideways from fairly high up, I only want a box that is good enough for the kindof intense use i'd make of it, and at a price I can afford (I am a cheapskate! i want cheap things ) The springs can be geared to 4kg force, they're optional grades that are all compatible in the same format. The complete design will be tweaked in a collaborative autocad design review with EE experts in alloys and physics and metal pressing and so on. cheers m8.

The tone seems as if you interested in constructive feedback? And let me say upfront that I appreciate your efforts and sharing.

If so, a few things that jump out to me.
1) Scale. My powerwall is 9,000 cells and counting and any kind of system like this falls due to additional cost / cell. To me - these kind of systems may have a place but not for powerwalls (1,000(s) of cells).
2) Claim it takes 6hrs to build a pack - not true at all. Takes me maybe 1 hour to assemble/solder a 60p pack. I would tone that down / maybe focus messy buss-bars, solder, OR learning to spot-weld etc instead of time.
3) Kind of skipped over the BMS and multi-BMS arrangements needed if doing a lot of smaller boxes and aggregating into a larger system. Would be better if you had actual BMS mounted in the box as part of the design? or perhaps design for common ones people can buy such as DALY or other (not pushing DALY).
4) Not sure about compression contacts - especially for 'fairly dirty' recovered second hand cells where the + / - were difficult to smooth out. Buying new/clean cells is kind of against what most DIY folks do as far as I can determine.... Maybe a roughed up contact plate?
5) Maybe have a LifePO4 solution - especially for smaller 12v (nominal) solutions! as 18650 is no good for this Maybe cylinder LifePo4 cells like A123s?
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5) Competition - @jehugarcia is quit a ways down the buy/assemble path and he's addressed several of the issues above by integrating BMS(s) and physical stacking etc - https://jag35.com/products/18650-battery-module-diy-pcb-kit?_pos=13&_sid=6bfc682ef&_ss=r *Not pushing @jehugarcia!* Just offering as info in case you haven't seen it.

I don't mean any of the above to discourage you're efforts - but perhaps things to think about as you hone your sales pitch

Defenitly a neat idea, but a lot of marketing speech with tons of buzz words and with many exaggerated examples.

There are however some real issues with the product in my opinion.
Security, you have a potential hazard in a box, with no countermeasurements, no cell level fusing, no way to prevent a thermal runaway and no BMS.
Longjevity, springs are known to wear out, 18650's dont really like their 2.5-4.2v range, a BMS with user settable settings/templates would be nice.
Changes in temperatur weakens plastic and can cause it to crack over time, especially the suggest 50 years life-time of the product. Maybe an alternative out of aluminium would be good.
The closing mechanism can be made a little easier, by adding a simple hinge mechanism, like in those battery holders in your average remote that can be secured with some screws.

But price is the biggest factor probably, scaling it up to thousands of cells wont really make it a feasable product. However, those white 18650 holders look neat and i could use those in the future for my 18650 packs.

Additionally, i want to point out that you have many outright lies on your website....
No thanks, i'll avoid your product all together with such a shady start.

OffGridInTheCity said:

1) may have a place but not for powerwalls (1,000(s) of cells).
2) Claim it takes 6hrs to build a pack
3) Kind of skipped over the BMS
4) Not sure about compression contacts
5) Maybe have a LifePO4 solution
Competition - @jehugarcia is quit a ways down the buy/assemble

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Hi, Thanks for the suggestions!

1) flecked cells: The video has studs of nickel for contacts, I can swap those with tumbleweed balls of wire compressed into a disk shape, so it's like braided disk which adapts to flecks. Flecks are a hassle for everyone and the 18650s are nickel-coated steel to prevent rusting, so it's not ok to sand the nickel off, you can blast them off using a sander which is protected by a 100 micron spacer, so you'd press the battery straight on the sander and in 2 seconds the fleck would be only 100 micron big. Any ideas to design a fleck sander?

2) 9000 cells : if you can 3D print the box inlays and bond them onto a transparent plastic board, add compressed tumbleweed disk contacts and my insulators with thermochromic pigment in lines of 30 or 40 batteries, so 40x40 is about 1600 batteries... I hope that the thermochromic will tell you if a battery has gone old and it's temperature is a bit high, dunno honestly. I'd offer DIY ideas rather than expensive deals honestly.

5) I took 15 hours to build a 112 pack recently including the BMS. It has some complex routing. Cutting shrink rap and fitting them and melting was 1 hour, hot-glue was 40+ minutes, welding at 40A took 8 hours, fitting the bms at 40A took 1 hour, and physical protection and padding took 1h30. The one previous took like 15 hours too.

3) I intend to offer very complete LiFePo4 options in 26650 format, what are the cheapest and best LiFePo4 cells?

2) For the BMS there is 70x20mm optional space at the front of boxes by default, you have to uncheck if you don't want a big BMS space, Sorry I forgot to illustrate BMS cos it's fiddly, i thought it was trivial, sorry i'll add illustrations to a new video soon. https://batgroupcraft.com/misc-technical

Oberfail said:

Defenitly a neat idea, but a lot of marketing speech with tons of buzz words and with many exaggerated examples.

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The top cover can't use a hinge! the springs are incredibly strong! 20x15 1KG springs is 300KG of downforce! try getting a hinge lid on that.

They're primarily aimed for helping people in India and Vietnam that live in these conditions and swim across the pacific, so the lid is designed for maximum vibration, it can be clad in steel for humid monsoon conditions for motorbikes and rickshaws, while just being a fairly thin box.

They use some ABS for electric kettles. I want FR4 board and see-through HDPE / ABS. Lego bricks are ABS they last 50 years.

Security wise, it'll be delivered with yellow stickers and big warning to assemble outdoors for the 1/10k users that think it's a toy. https://batgroupcraft.com/misc-technical, optional for DIY kit versions. sry i'll add BMS illustrations on another video.

Cell Level Fuses: View: https://www.youtube.com/watch?v=UFo1B0MGnpE

Just a fun design, not saying it's useful for 2021 quality batteries and their built in protection, and it doesnt work for old batteries with flecks, so...

Additionally, i want to point out that you have many outright lies on your website....
No thanks, i'll avoid your product all together with such a shady start. ????

That's mean and you should be more specific, I don't think you know what you're talking about. I am from a 20 years background in designing EV's. What lie??? where did I lie? Would you recommend an RV guy to buy a non-recyclable battery pack that is more expensive? Who do you think i'm doing this for, it's for the children and adults around the world whose streets have 18 times the pollution levels of NYC. Sorry that the audio dubbing has some claims that you don't like, was pressed for time.

Show me science that a tempered 1kg spring will last less than 50 years before being reduced to 50% of it's compression force?

First of all, thanks for the answers. Now i have more insight into your product and it now makes sense, why you did not opt for a hinge mechanism.

BatGroupCraft said:

That's mean and you should be more specific

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Li-ion is 6 times lighter than Lead-Acid and LiFePo is 3.5 times lighter than lead equivalent batteries. They last about 5000% longer and cost the same.

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Where is any proof of that? A Lead-Acid battery that is being taken care of, can last for tens of years. The average car battery when taken care of, can also last over 5 years easily. Longer, perhaps, but not about 5000%.

Source: https://batgroupcraft.com/faq-basic

97% percent less work to craft a battery

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How did you measure that? Soldering my 14s32p battery, containing 448 cells and a BMS with the wrong tools, took me only about 8 hours. With nickel strips and a spot welder, it would have probably only took 2 hours but been more expensive and using more conflict materials which i want to avoid. Stuffing one of your box with an equivivalent amount of cells, wiring up the bms and so on would probably take half an hour aswell and would use a lot of plastic, which i try to avoid aswell.

Source: https://batgroupcraft.com/

Technical simplicity reduces lithium price 20%

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You probably mean assembled lithium batteries and not the price of raw lithium.
If i'd were to get a plastic box, some 18650 holders and a bms, i'd probably still end up cheaper than going with one of your boxes. Your box however has the adventage of needing less time and work to assemble and its easy repairable if some cells wear out or the bms breaks.

Source: https://batgroupcraft.com/

The lithium packing enigma has been called "the holy grail of lithium". Engineers were emphatic: "Who will bring an easy lithium system?" They commanded me to this mission.

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I've never heard anyone saying any of those claims.

Source: https://batgroupcraft.com/about-me-1

I was taken to an unsolvable enigma, an impossibly tough challenge. A friend said “don’t give up your quest”, so I continued, aiming to deliver a perfectionist, flawless, easy lithium crafting box.

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If it were unsolvable, why are there plenty of solutions for it, even long before your solution to it?

Source: https://batgroupcraft.com/about-me-1

BatGroupCraft said:

Would you recommend an RV guy to buy a non-recyclable battery pack that is more expensive?

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Obviously not. I'd recommend them to diy a LiFePo4 system themself. Lithium batteries can already be recycled and i know a moraly great company, that has not patented their way of doing it, so others can copy it and are very open about their recycling process.


The way you are marketing your product & yourself, is a way i just dont like. But dont get me wrong, your product is neat and there are defenitly usecases for it. It has plenty of upsides. Its far from perfectionist & flawless in my opinion, but its a step in the right direction. It is reusable, probably good recycable due to its low build complexity and usage of mostly the same materials, easily to work on it yourself and it will be open source instead of the industry standard sealed black box with unkown contet. Overall, a good product.

The last thing i would add is, have you went to a recycling plant and asked them, if they would be able to recycle your product well and how you could maybe improve that aspect?

OK i am learning that powerwall builders have different technology than EV builders, I don't understand your specialties very well.

I wrote the FAQ off the top of my head, OK i'll be more precise thanks:
LG MJ1 on my ebike:
Density gravimetric theoretic = 261.00 Wh/kg
Lead Acid gravimetric density = 41 Wh/kg... https://sinovoltaics.com/wp-content/upload_folders/sinovoltaics.com/2019/09/Picture1.png

lithium has 10 times the volumetric density and my ebike has 6.2 times the gravimetric density of lead.

97% percent less work to craft a battery... did you see the sunset at the start of the timelapse? It was day when he started that video, the sunset only took 7% of the video. Sunset until twighlight takes 30 minutes, so he was working for 6 hours!!! I also counted the numbers of frames and his FPS and multiplied it. I have made two strong complex ebike batteries and cutting,wrapping,glueing,soldering,bmsing,wrapping,padding, took me 15 HOURS for 112 cells. It's much more complicated to weld automotive than 24V mega arrays which aren't vibration proof!!!

Technical simplicity reduces lithium price 20%... Yeah i take that back, my box reduces lithium price by 30%: The welding process means consumer batteries are welded off-site by an EU techinician / in China... Subsequent shipping is really expensive. An EU technician will charge consumers 150 to weld and glue and wrap 100 cells for an ebike/motorbike/camping car, it's super complex, So they're paying 250 euros of cost on top of the 250 they paid for the battery. ... My box only costs 90 Euros if I can make it a commodity, So instead of paying 250 to third parties... you pay 90 AND the box is re-sellable, so you can resell my box and reclaim all your money!!! And it's re-usable, so the second time you use it you get FREE packaging costs... Look at the prices!!! Why is it from china? because the welding is very expensive. https://www.wattuneed.com/en/lithiu...hium-ion-battery-10kwh-48v-0712971135673.html they're asking 6000 EUROS!!! for a EU built box,People can buy the same thing from me for only 3000 euros, plus you can resell the box for 500 euros if you get a see-through thermochromic steel clad one.

The lithium packing enigma has been called "the holy grail of lithium". I've never heard anyone saying any of those claims.
If you never heard it, perhaps it happened anyway. Be fair man! no one is arguing with it being called the holy grail there. IT IS!

If it were unsolvable, why are there plenty of solutions for it... There aren't: Nobody can build a lithium battery in 15 minutes which you can put on an ebike, which is dustproof and which can withstand years of rocky roads. Only someone who wants to burn their cherished Ebike would risk a ******* on there. (HBPowerwall even sensored Vr..zend that's proof it doesn't exist!) Look at the alternative company, he charges 130 dollars for 9x 18860 cells! he sells to dozens of foolish lampost and bus shelter integrators. Help me out! i'm trying to lower the price and raise the quality for everyboday. please support me and stop these rip-off technologies making people MILLIONS!!!! yes, that guy got a 2 million loan from the EU for that BOX!!! Help a cheapskate indie ecologist! i'm an engineer!

Please show me a single other dustproof, robust easy build affordable box? This is it, i am the only one cheapskate enough to make it affordable.

I don't like the way i'm marketing myself either, I'm very nervous, camera shy, I don't have a filming location, i struggled for a coherent sounding dub... and maybe went OTT about the performance because I code formants, I like the word. I prefer to have a jolly team to film for me near Le Massif Central, i am a designer i shouldn't have to do this video selling this product, but at least you can see my motivations. It's honest and it's to help the planet and i want to break even, i don't want to rake up cash because i want to do other companies after.

BatGroupCraft said:

Hi everybody, I am a big fan of powerwalls and home arrays of lithium..................................................................free boxes and use super high quality materials like FR4 to save lots of time building home lithium banks.

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@BatGroupCraft.
I think your design and concept has its merits, especially for EV/ bikes and looks to be useful for many mobile applications.
Considering your statement" I am a big fan of powerwalls and home arrays"
then what you said below is one of your best statements.

BatGroupCraft said:

OK i am learning that powerwall builders have different technology than EV builders, I don't understand your specialties very well.

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I do not think for a large stationary powerwall this concept /design is the answer. For most of us the most time consuming process is harvesting, processing and sorting out the cells we want to use in our powerwalls. Using my experience as an example it took me from August, 2019 to May, 2020 to build my first 14s80p battery. That was processing 10,000+ cells to get 1120 good ones. Granted I was very picky and had some initial bad used battery pack choices. Hence the cell quantity. Once the cells have been chosen and sorted into their individual packs, Spot Welding the fuse sheet and soldering the bus bars to the pack is maybe a 1hr affair per 80 cell (4 welds per cell) pack x 14 so 14 hrs total for a 10kWh Battery including the time for the spot weld probes to cool off.
The second pack took way less time August 2020 to December 2020.
For me the boxed design pressure/spring contacts is somewhat concerning as it does add resistance to the whole mix and resistance = heat however little it may be in a non vented/sealed box with 80 cells in it has me a bit concerned. Notwithstanding an array of 14s80p X4 equates to 4,480 cells. For me a mechanical and electrical contact is paramount for safety and low resistance. For those of us who do live in a changing season climate we also have to think about heating/cooling our cells. I do not think heating/cooling cells in a sealed environment would be as easy as an open cell architecture to allow airflow between the cells.
Wolf

Wolf said:

it took me from August, 2019 to May, 2020 to build my first 14s80p

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Those are awesome pictures, cheers for the information!!! nice crafting. I figure that I can help people who want to build an array using 26650 and 32650 lifepo4 in just 2 days of work rather than 8 months, at a cost of less than welded lithium, and the owners need only buy new batteries in 12 years and it will take them another 2 days to refill free boxes to revamp the array.
The building time for my version is about 3 kilowatts every hour using 26650, so you can build a 50 kilowatt array in 20 hours very easily, which are guaranteed 4000 cycles, Your arrays are nearly free, so that's amazing.
For electricians it could be competition to Tesla boxes which take them 2 days to build using generic cheap components when they are putting buildings off grid. I expect car batteries will be even faster for that in future, so this tech is still aimed towards fablabs, prototypes, motorbikes, camping cars, boats, i don't want to make a profit, honestly the aim of this company is to let me get into much more complex startups based on algorithms, robotics, education tools for developing regions, gardening robots... This is more of an open source starter technology.

BatGroupCraft said:

I figure that I can help people who want to build an array using 26650 and 32650 lifepo4 in just 2 days of work rather than 8 months

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Eeeh not really. He took 8 months, because he had to disassemble the used battery packs, test each single cell, noting the results down, calculating which ones to use and which ones not and after that, he assembled the pack. Thats the drawback when using used cells, but its a heck of a lot cheaper. If he were to use your box, he'd still need to test all cells individually and so on. Same with me, it took me about 2 months to test my cells, but just 8 hours to assemble it.

BatGroupCraft said:

the owners need only buy new batteries in 20 years

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The thing with LiFePo4 batteries is, their cycle count is given with a 80% DOD (depth-of-discharge). Charging them to 90% and discharging them to 10%. Most BMS's however go the whole range of 100% to 0% with any type of battery, often even above and under those limits, that damages the cells significantly more. You need to provide a custom BMS, that keeps the cells within their 80% DOD state and not the 100% one.

BatGroupCraft said:

For electricians it could be competition to Tesla boxes which take them 2 days to build using generic cheap components when they are putting buildings off grid.

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There are plenty of differences between your box and a tesla power wall. Cooling is a big factor for example and propriotary protocols between their own systems. In germany for example, you cant just install your own Solar + Power wall and call it a day, a certified technician has to approve of it and thats *very* hard to do with a self build system. Hence why companies get away with high prices for their products.

BatGroupCraft said:

the aim of this company is to let me get into much more complex startups based on algorithms, robotics, education tools for developing regions, gardening robots... This is more of an open source starter technology.

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Your next thing, could be a BMS fitting to your boxes. One that keeps the cells properly in check. There are many quirks that our round friends have that you probably dont know about and many ways, they can be improved with the proper controllers.

BatGroupCraft said:

HBPowerwall even sensored Vr..zend that's proof it doesn't exist!

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HBPowerwall sensoring that company has nothing to do with their product. It has everything to do with their ethics and spam tactics. They have an intriguing system for sure. But they need to learn how to communicate and not be bombastic to other solutions.

I had a quick look at the project and watched the video. Yes, I like it. Like the design. Like the idea and the result. For bikes it's seems great.

But for my soon-to-come powerwall I do want individual fuses for each cell.

I do think I'd choose your box for my home appliances. I made a small power backup box for my router using a recycled plastic box (any used box is good for me). With your design I could have a nicer container and my wife would be happier! But you should leave me some space to insert a 5x7cm PCB (also possibily 2-3cm in height) somewhere.

[Quick EDIT] I see everybody got heated up with this stuff! lol I read your comments on the YouTube channel and that you did think of BMS support. I like the communication, too, and the kind way you speak.

I understand Korishan and Oberfail. I did notice that V...zend had hidden every photo of the metals inside their equipment in all the sales material.

Grazie Italianuser! I studied some recyclable fuses here, it's just un idea stravagante, it would be as durable as a car fuse and reusable:

View: https://www.youtube.com/watch?v=UFo1B0MGnpE



Yes there'll be many space options for the BMS, I'll draw lots of images, here is a basic idea of the current BMS spaces: https://batgroupcraft.com/misc-technical, There will be space for a 20x7x15cm inverter if folk wish, it's literally a glue-together box which you can arrange in any way you like, you can have 25% of equipment and 75% of lithium if you wish.

Don't take this wrong but I've to admit with the others opinions. I've walked this path, but on some point you have to choose between functionality (including security, useability and all the things) and the costs. Some things you can't ignore (like security) but the others have to give up, because of additional cost. Well, the costs always will be higher then: grabbing the soldering iron or spot-welder and make it on yourself, especially for PW with 1400cells inside. If the costs are higher there have to be some advantages, i.e.:
- easy to assemble, repair, service, etc
- scalable
- no design flaws and "dummy proof" is a must, this stuff buying beginners not advanced ones
- additional functionality like fuses, bms, maybe voltage monitor, etc
- and... the costs still should be low

Try to look on my project, maybe it helps you with some ideas:
(Still working on the project in my free time... so new version on the way)

roman2 said:

Try to look on my project, maybe it helps you with some ideas:

Battery sandwich - different approach to DIY powerwall (based on 18650s)

Hello, at the beginning I'd like to thank all the contributors in this place. (and sorry about my english in advance) According to DIY powerwalls which are build on PCBs, I saw couple different designs (on aliexpress, etc) but none off them was 100% compliant with my requirements ;) So I...

secondlifestorage.com

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Cheers Roman, that's very interesting , awesome design , Very nice equipment , There a guy selling a pcb based sandwitch for 9 cells at $130 on Conrad.fr/digikey electronics, only difference is that it's got a plastic shell, lol, put em on conrad at 25 lol

BatGroupCraft said:

Pre launch video for a new technology via crowdfunding

Hi everybody, I am a big fan of powerwalls and home arrays of lithium. Do you think it will be OK if I post this technology to the discussions forums? Please sign up on the project home page if you want to watch the launch day as it happens, as soon as I have enough subscribers www.batgroupcraft.com Please Sign Up!

here is a technology so that people will be able to 3D print templates for free boxes and use super high quality materials like FR4 to save lots of time building home lithium banks. I'm still working on the video, have to add some BMS illustrations.

Click to expand...

Have you measured the additional internal resistance introduced by a purely mechanical contact between a cell and busbars? I did some experiments on this and measured that when I used spring contacts like these: https://www.aliexpress.com/item/32884289489.html this added around 100 mOhms to the internal resistance of each cell (spring contact on one side,"flat" contact on another side). I see that your system is different where the cells directly contact a flat metal surface and the springs just provide the push force however I expect the electrical contact to be sub-par compared to welding or soldering. Have you checked this?

Additionally, for cell from diassembled packs there is often residue from old nickel strips left on the cell contacts making it even more difficult to properly connect them using mechanical force alone. In your demos you use new cells with clean contacts.

In overview I think you idea is not a bad one and will have use cases.

Yes the conductivity of spring alloys is less vs copper equivalent (IACS) : 10% for spring steel, 22% for copper-beryllium.

The aliexpress springs are 1mm steel. 1.5 Amp current rating, (18AWG equivalent for carbon steel)

If my design uses pure Nickel, then the contact is rated at 35 A (20mm²), while the busbar is 50 A... So the high resistance point of the contact is the 5 microns at the rough surfaces of the metal.

For those 5 microns, the conductivity can be reduced to only 1%. If you average the maths:

5 microns at 0.35A rating + 2000 microns at 35A + 10cm at 50A = average ampacity is
1.75 + 70,000 + 5,000,000 / 102005 = 49.7 A average theoretical for my box.
0.875 + " + " / 102025 = 49.69 A if the contacts from my box are very degraded (25 microns at 0.035A )

From anderson powerpoles, we see also that a contact 4 times smaller than my box has 40A max rating. What is fascinating for me is to imagine the electrical lightning that happens at the contact surfaces, even if the lightning only happens for 0.01 milliseconds every day at 40A lol. That means that there would be 1 second of lightning every 10,000 days. omg! The lightning is less because the busbar is still in mating with many of the neighbor cells.

I test the box at 1700W for 54 cells using thermal monitor of wires, the wires were cold, the limit was from the 18650's, I have to buy vaping cells to test the 2400W theoretical limit. that is comparison of elemental.

The most unreliable element of the box is the 5 microns of the contact area, which requires adaptive metal and very serious engineering lol.

I think this is absolutely fantastic and its a bit sad to see some of the reaction here. Possibly because of the slightly wacky website I'm guessing

I've been waiting for someone to engineer something like this for years, it just seems so obvious to me to make a pack modular and easy to assemble. I've built a small fused eBike pack and it took me way more than 6hrs

Now what's your plan to get these into production? I will be your first customer if you want

Again I would like to say how awesome this is.