DIY E bike 72V 20H Battery build - Part 2

Part 2 of the battery making of.
I did the mold of copper sheet, and star the welding process. Copper nickel sandwich method not used very often but a great option for high power batteries.
Hope you like.
Subscrive.
Any questions ask on comments.
I’ll soon to put videos of the ebike also
Part 3 - • DIY E bike 72V 20H Bat...

[@sreekumarUSA]

Thank you for exhibiting copper and Nickel can be spot welded. I learned this technique from you. Thank you once again.

[@trufinv]

Thank you for the video. Using copper sheet like this seems like the way to go

[@norbithehun]

Thanks for the video. Use neodym magnet on the top to hold in place the stripes. For me it is working great.

[@e-biker8406]

I thought doing that but the magnets I have are big, I was a afraid of shorting the battery

[@carlosleon7683]

Thanks for the video. Do you know if this method would work with the copper strips that they sell for putting the batteries together?

[@slappy8714]

Thank you very much for this video. I am very interested trying this method (with the copper). Something I was considering was using silver solder to braze nickel strip to copper busbar, then weld the nickel strip to the cell, but method looks much more efficient.

[@e-biker8406]

Thank you. This is a very straightforward solution and if you have a good spot welder will be even easier to do. 😊

[@ericklein5097]

that would be putting the nickel as the primary interconnect material that the current first has to flow through before getting to the copper which defeats the purpose of using copper. There might be some slight gain if the path of least resistance is through the nickel to the copper across the cell then down the copper into the nickel and into the cell

[@hadowman6847]

nice

[@luizcarlosmagno77]

Trabalho impecável! Like garantido, ganhou mais um inscrito!

[@e-biker8406]

Obrigado Luiz, os vídeos estão meio toscos mas o jeito para filmar não é muito 😂

[@beaubarton2646]

Hello, i really like this 3 part battery build. Im basically using your videos as my bible as i build my own batteries. im making 3 separate packs to suite my ebike (x3 72v packs joined in parallel)20s2p x 3 in parallel so 120 21700 cells. combined its 72v 25.5 AH pushing upto 250 amps but i only need draw upto 90amp & 120a peak. Thank you so much for your detailed videos. My ebay kkmoon 5k spotwelder didn't last and lacked punch, so i bought a Kweld and use my car battery for power supply. I really like the copper sandwich. 2 questions please; 1 have you thought about a protective paint or film to prevent copper oxidation? im thinking spray paint or paint on tape may be enough to set and forget. 2. how much current in amps are you demanding from the 0.1mm copper? im asking 30 amp peak from each cell / series connections cheers

[@e-biker8406]

Hello, this is part 2 :P I'm really happy that my videos help the community and became an inspiration, I'm always glad to help. For sure those ebay spot welder are made for small jobs, not big battery builds, Kweld will pack a punch. 1 - I thought about the copper copper oxidation, probably the strip will create a oxidised layer at the surface, but I've no intention of using in rainy wheather mostly will be used in good sunny days, and battery will be stored at home. the copper is covered with tape that should provide some protection. To fully protect you probably need to paint both sides of the copper. 2 - my peak power is 80A, limited by the BMS unit, making some calculation a 0.1mm * 10mm copper strip could handle 15A, I've used a sheet 0.1mm and 105mm wide, that would be like having 10 strips of 10 mm x 0.1mm giving a 150A of constant current capacity, peak will be much higher between parallel groups. You have 6 cell parallel, 120 / 6 = you're pulling 20A per cell in peak and just 15A in constant.^ I hope it wasn't confusing.

[@juvenalgonzalez8756]

What copper size sheet do I use if I want to run 100-150amps ?? Please help

[@CryoGenic]

Great compact pack design , have you had any issues with the hot glue withstanding the vibrations , I see you stripped off the outer casing of the cells did you do this to allow better adherence between the hot glue and the cell , I thought this would risk a short , I am tempted to use the honeycomb cell holders I’m also using 21700 so will be slightly larger

[@e-biker8406]

Hi. I didn’t stripped the outer casing, the plastic is transparent, the hot glue is just another layer of security, the battery was tightly secure with black tape and some abs plastic sheets

[@e-biker8406]

The cell holders will make a bigger battery, I needed to save as much space as possible

[@ubrunus]

Olá, parabéns pelos videos, vão me inspirar para a bateria que estou a projectar ( para uma e-moto Citycoco, 60V 16S 8P ou mesmo 10P, podes por favor me informar onde compraste o BMS? Obrigado.

[@e-biker8406]

Espero que seja uma boa inspiração, qualquer coisa que possa ajudar diz. AliExpress 😊 Armazéns europeus, costumam ter alguns BMS em stock

[@jamo9000]

Fantastic video. I have the same and didn't realise it could successfully do copper. It struggles with 0.15mm pure nickel. So this is a great option. Is the nickel you're using to sandwich pure 0.1 nickel or is it nickel plated steel? As its just used as an anchor and not current flow wouldn't you get better welding results using nickel plated steel on top of the copper as its easier to weld? Thanks for showing this and what the the little BIFRC welder is capable.

[@e-biker8406]

Thank you, You're right nickel plated steel for this setup is the best option, because it's easier to weld, it's what I've used in the video, 0.1 mm nickel plated nickel :)

[@leonardoantunes5910]

Olá quantos mm tem o copper sheet? E qual spot welder usas para soldar cobre? Muito obg excelente conteúdo! :)

[@e-biker8406]

O copper sheet tem 0,1mm, tem condutividade suficiente para muitos amperes por ter uma área grande. O spot welder foi um barato do aliexpress. Usando tira de nickel plated steel 0,1mm solda fácil, mas o spot welder aquece muito, tem de se fazer o trabalho aos bocados.

[@archietheproto7706]

The nickel does add a bit of conductivity, the parallel strips should have slightly more conductivity than the series

[@electrikeseb1247]

Salut j ai essayer de souder de cette façon il y a rien qui tiens j ai mis la puissance max de ma pointeuse ça tiens pas comment fait tu ?

[@DG-XTREAM]

Good Morning, I have Molicel INR21700-P42A cells which can deliver up to 45A in discharge according to the manufacturer I make a 20S 10P 72V 42AH battery. I would like to use 400A in peak but I don't know how to choose the thickness and the way to connect my cables. Do you have any advice to make a safe battery? I had chosen 0.1mm x 30mm copper but I don't know if it is suitable. I have 40A per cell.

[@e-biker8406]

Do you want to use 400A in peak?? That’s a lot. That’s more 28000w of power does your engine, your frame handle that kind of power and torque? I can’t tell you for sure if the copper sheet will handle that kind of power, if it does only for short time because is gonna heat up. I’ve used car jumper cables they handle a lot of current. I’ve a video soldering the cables, check part 3

[@ericklein5097]

Take the thickness multiplied by the width and and compare that to copper wire cross sectional area. If you have say 16mm2 because your copper is 0.1mmx160mm then that is equal to 16mm2 wire which is 6AWG. That is good for 60-100A. You don't have insulation on your copper strip so you have to think how comofortable you are with your copper getting hot like silicone wire is rated for 200 Celsius. I would recommend using the numbers for 75 celsius

[@vigolivenca]

Viva, obrigado pelo video bem detalhado. Onde comprou as folhas de cobre?

[@e-biker8406]

Foi na Amazon, copper sheet 0.1mm 😊

[@vigolivenca]

@@e-biker8406 Viva tentei seguir a mesma estratégia de soldar o cobre de 0.15mm com um soldador "spot weld" comum, usando uma tira de nícel por cima, mas com o cobre não solda, com o nícel funciona sem problemas. Alguma ideia como possa funcionar? vou ter de soldar com solda e ferro de soldar :(

[@e-biker8406]

@@vigolivenca talvez 0,15mm seja muito grosso, penso que usei 0.1mm. Mas a tira de nickel, não deve puro nickel, deve ser nickel planted/ banhado a níquel, senão o puro é demasiado bom condutor

[@vigolivenca]

@@e-biker8406 obrigado, já encomendei todas as espesuras a ver se alguma combinação funciona.

[@sophanhator5087]

what kind of copper strip did you use ( Thickness and dimension) , and where can i buy it online?iamonio

[@e-biker8406]

Hi. It’s a 0.1mm copper sheet, bought it on amazon. Search on amazon or ebay, this sheets are used in crafts.

[@lbabacar8653]

@@e-biker8406 thickness of the nickel ? Plated or classic ?

[@e-biker8406]

@@lbabacar8653 it’s 0,1 nickel plated. Like I said in the videos the nickel strip is just for the weld to stick, has no function on conductivity.

[@tofanalexander]

I tried the same method and the Copper is not sticking to the cells. Tried it between two nickel strips - same thing - it won't stick!

[@e-biker8406]

Hi. Maybe your spot welder it’s not strong enough. Make sure that is not pure nickel, but nickel plated (has more electrical resistance) and the strip must be thin. Put just copper in contact with the battery and the nickel strip on top.

[@plojm123]

What spot welder do you use

[@e-biker8406]

some generic one, from ebay or aliexpress. Like this one: pt.aliexpress.com/item/1005004234546513.html?spm=a2g0o.productlist.0.0.17d8771bUGvESU&algo_pvid=ab38b91a-f956-4614-aa01-4ad0f680fe1a&algo_exp_id=ab38b91a-f956-4614-aa01-4ad0f680fe1a-0&pdp_ext_f=%7B%22sku_id%22%3A%2212000028474527257%22%7D&pdp_npi=1%40dis%7CEUR%7C%7C26.0%7C%7C%7C%7C%7C%402103143616515682623232257e0973%7C12000028474527257%7Csea

[@mustafataha7305]

Why do you have to avoid the center of the negative battery terminal?

[@e-biker8406]

Hi, that have to do with the struture of the battery, inside the battery the lithium sheet is roll, like a paper roll, so in the dead center is hollow, makes that particular piece of the battery more fragile, welding it may causa some damage to battery struture. You can see in this picture what I've said: www.researchgate.net/publication/324511614/figure/fig6/AS:615135848718340@1523671223650/CT-scan-images-of-a-cylindrical-lithium-ion-battery-a-axial-view-b-front-view-c.png

[@mustafataha7305]

@@e-biker8406 oh I see, thank you so much for the explanation. Building a battery, I'll be sure to avoid the center

[@Doctorbasss]

This is because the tab between the jelly roll and the cell tab are connected thru a thin foil ribbon that is already welded inside the cell can to the negative center.

[@Ercani]

Is that pure nickel or nickel plated steel ?

[@e-biker8406]

Hi. It’s nickel plated. But the strips are just to turn the spot welds possible, has no function in the conductivity, in this case.

[@juvenalgonzalez8756]

What type of hot glue is that ? I’ve been trying to avoid using brackets but my hot glue keeps coming off

[@e-biker8406]

It’s just normal hot glue. Make sure it’s hot enough to become more sticky

[@juvenalgonzalez8756]

@@e-biker8406 thanks will do , I know I do have a cheap dollar store must be the issue

[@e-biker8406]

Mine it’s a cheap one from aliexpress. Make sure the strip is 0.1mm and it’s nickel plated not pure nickel

[@juvenalgonzalez8756]

⁠@@e-biker8406 i have 0.15 nickle strips would that work ? I have a 5000w welder from ali express as well please let me know

[@juvenalgonzalez8756]

@@e-biker8406also where did you buy the copper foil ? And if it’s 0.1 how many rated amps is it for ? I’m looking for something to hold 150

[@akinnon2000]

Mine dont seams to stick, maybe i need more power ?

[@e-biker8406]

Mine is a weak spot welder from aliexpress, maybe is the thickness of the strips, 0,1mm nickel plated (not pure nickel) and 0,1mm copper, if I remember it right

[@publicname515]

How many amps can this much copper handle?

[@e-biker8406]

my peak power is 80A, limited by the BMS unit, making some calculation a 0.1mm * 10mm copper strip could handle 15A, I've used a sheet 0.1mm and 105mm wide, that would be like having 10 strips of 10 mm x 0.1mm in parallel making the math in theory gives a 150A of constant current capacity, peak will be much higher between parallel groups. Hope it helps

[@publicname515]

@@e-biker8406 Thank you, which welder are you using?

[@e-biker8406]

@@publicname515 Was the cheapest welder in aliexpress, not ideal for a big work like I did but it did the job

[@ericklein5097]

Compare to the cross sectional area of copper wire. Use the ampacity charts for 75C insulated wire

[@akinnon2000]

ohh... so all i have to do to spot weld copper .. is place a nickel strip over it ? Damn... thanks

[@TheycallmeMrWonka]

*0.1mm Nickel plated steel and 0.1mm copper unless you have a very powerful spot welder.

[@Maxttor]

Eu iria montar a célula sem esse adesivo redondo com furo no meio, mas parece importante

[@e-biker8406]

Caso a célula só tenha invólucro plástico, sim, eu recomendo porque em caso de aquecedor o plástico derrete fácil e pode haver curto circuito. No meu caso, acabei por depois retirar as que pus porque a bateria já trazia esse papel isolante e não fazia sentido duplicar e dificultava-me a soldagem dos contactos.

[@Maxttor]

@@e-biker8406 Tive uma ideia brother pra fazer isso ai na mão, que material seria isso, é somente papel?

[@e-biker8406]

@@Maxttor o material é papel mas é um papel compacto, não é igual a papel para escrever.

[@e-biker8406]

Em inglês chamam fish paper, provavemente é um papel bastante mais compacto, aumentando o isolamento elétrico

[@Maxttor]

@@e-biker8406 desmontei um pack com problema e dei uma analisada, é um papel grosso e com superfície granulada por cima de um adesivo plastico fino, é um bom isolador, no meu caso vou usar o divisor plástico de encaixar baterias que mantem uma distancia fixa entre elas e elimina em grande parte a possibilidade de problemas.

[@electrikeseb1247]

Salut tes cellule c est des 21700 30t remis a neuf de chez nkon ?

[@e-biker8406]

Yes. They are.

[@electrikeseb1247]

@@e-biker8406 ok as tu fait des essai avec ta batterie les cellules tiennent bien dans le temp ?

[@e-biker8406]

@@electrikeseb1247 nkon says the batteries are not used, were just soldered for baterry packs and then dissassembled, but were never used

[@electrikeseb1247]

@@e-biker8406 oui arjan me la comfirmer c est juste que pour le coup pas trop d info sur l année et si elles sont grade a

[@electrikeseb1247]

Salut quel soudeuse tu utilise ?

[@lanecole1217]

can you build me one?

[@e-biker8406]

Where are you from?

[@marvempyreanlife]

That's a dangerous battery where's the wrap for the cells

[@e-biker8406]

It have a clear plastic wrap, probably hard to see in video.

[@anhbababa6530]

A fool is trying to make a bomb. Get knowledge before you do something

[@e-biker8406]

And Why is that?? Can you explain??

[@anhbababa6530]

@@e-biker8406 You pair the batteries that have been stripped bare with candle glue, so when using, the battery is hot, so it will lead to melting glue and short-circuiting. Please keep electrical safety when doing something.

[@e-biker8406]

@@anhbababa6530 batteries are not stripped, they have a clear plastic wrap, yes the hot glue isn’t ideal but they batteries were wrapped with thermal tape all around, and after protected with a hard plastic securely tighted with strong tape and put in a hard case tightly fitted, movement between batteries will be no issue. Despite that batterie will be running at an a lot lower amp that they can handle, so it maybe be warm but not nearly hot enough to melt the glue.

[@TheycallmeMrWonka]

None sense. You exagerrate and make assumptions. Is it perfect or the safest, no, but you are choosing the most extreme view based on a superficial viewing of what he has done.