Add-on e-bike conversion kit - Swytch or eBay kit?

[hemo]

I use a Boss Arduino mini spot welder cost $80 and works off a 3s 65/130 amp lipo.
Does up to 0.3mm pure nickel and can do 0.1/0.15mm copper with 4s.

https://endless-sphere.com/forums/viewt ... 14&t=89076


Recently acquired unused cells 100 PF Grade C and 50 PD Grade A cells at a £1 a cell. Ready to weld 2 packs up, PF is for a 140a 24v battery of 40.6ah/974wh for a power hungry and fast brushed motor. Copper sheet is going to be used for the current supply material. Currently using home made PF 48v packs on a CX bike and they have got some serious grunt to them best bang for £pound I have found yet. There are better 18650 cells but £ for £ these are the cheapest for a 10 cdr.

[Canuk]

I use a Boss Arduino mini spot welder cost $80 and works off a 3s 65/130 amp lipo.
Does up to 0.3mm pure nickel and can do 0.1/0.15mm copper with 4s.

https://endless-sphere.com/forums/viewt ... 14&t=89076


Recently acquired unused cells 100 PF Grade C and 50 PD Grade A cells at a £1 a cell. Ready to weld 2 packs up, PF is for a 140a 24v battery of 40.6ah/974wh for a power hungry and fast brushed motor. Copper sheet is going to be used for the current supply material. Currently using home made PF 48v packs on a CX bike and they have got some serious grunt to them best bang for £pound I have found yet.

Just a quick question, how many goes did it take you to produce a reliable, working battery? I'm interested because I might go down this route myself but the skills et required looks like it might take a bit of learning /trial and error to produce a working end result.

[hemo]

I use Endless sphere for all my research, it is a massive resource. I know we moan and berate yanks well at least I do but these guys rock when it comes to EV.
They don't have our 250w 15/20a ebikes they do power bikes, often 100 -200a current and 50 - 100mph.

A relaible working battery first time out, it's about reserch and understanding how current flows etc.etc.
You need to match the cells current capability to the needs of the ebike controller with a good headway so as not to stress the cells.
Paralell and esp series bus's need to be able to handle the current asked of the cells as well as using appropriate gauge wiring to handle peak current flow. Too thin wire rating and it gets warm or hot wasting energy that should be used at the motor, typically pure nickel common cell interconnector material can only handle opyimally 4.459a mm2 or acceptably 6.619a per cell, Commonly 7.5 x 0.15 nickel is used in diy packs due to the fact of getting a good weld contact without burning through and damaging the cell, heat hurts them. Soldering to cells is a no-no , Often 0.15 nickel is used as a double layer or copper is introduced to help with better current flow. Oem packs good ones will use 0.2 or 0.3mm nickel.

By the way sorry to say but that Sunko 737G you linked to is a pile of do -do, my very tiny Arduino spot welder will pee over it all day long, My one is built by a techy guy in Korea and was $80 delivered in under 10 days.
There is a similar copy of it being produced in Germany @ Malelectics.eu.
Full Arduino kit for car battery or lipo supply.
https://malectrics.eu/product/diy-ardui ... o-battery/

Making batteries is serious stuff, if you do it wrong KFF time and possibly serious results.
Practice on old crappy laptop cells if you mess up it don't matter.


If you want reading then look at these three threads to start with , bookmark them and refer to them. Read the spots off them maybe two or thre times over at least, I've been doing this for only 4 years. You never stop learning if you do leave the planet right now.
https://endless-sphere.com/forums/viewt ... 14&t=84412
https://endless-sphere.com/forums/viewt ... 14&t=68005
https://endless-sphere.com/forums/viewt ... 14&t=89076

[hemo]

Sincere apologies to AJ101 on this one as this has totally detracted from his OP and should be a separate thread may be mods/Graham or some one can move the techy posts to a new battery build thread ?


Going back to his OP all kits can produce more then 250w at the final drive the likes of OEM Bosch & Yamaha drive can and do up to 700w. I have 4 kits and 2 oem bikes and all produce over 500w at the final drive with one at near 850w.

The Swytch kit is having niggles with power pick up and vibrations with drive power the motor is a little weedy and for a lightweight solution, selecting the right kit will depend on the terrain you ride and you personal body weight and the type of bike you want to electrify.
Woosh bikes are good they won't just sell you any old bit of kit but willmatch one best to suit your needs if you give them all the facts/requirments to suit your needs. I have no personal link to them but keep on recommending them because they are good.

[Canuk]

Thanks for the link! I have ordered a set of 30 pulls from a brand new Bosch piece of kit which had a defective motor. And the spot weld is on its way from Germany.

How much did you budget for in materials for your first battery? Mine is looking like 180 euro so far, but a second battery should be around half that..

[MikeF]

2170(0) refers to the cell size, ie 21x70mm, as does 18650 (18x65mm).
Buying a 2170 cell will not guarantee you are buying the latest technology eg from Tesla or Samsung. However as the cell is larger it should have a greater capacity but probably that's all.

[hemo]

Thanks for the link! I have ordered a set of 30 pulls from a brand new Bosch piece of kit which had a defective motor. And the spot weld is on its way from Germany.

How much did you budget for in materials for your first battery? Mine is looking like 180 euro so far, but a second battery should be around half that..

I don't budget, if I want it I buy it.
I wanted to learn how to repair them fault find them for the future as battery prices even for medicre cells aren't heap.
Things like nickel strip,bms,kapton tap etc etc I buy from China on Aliexpress a very good seller is Ann/Annbattery the nickle is pure and not steel plated.

[Canuk]

Thanks for the link! I have ordered a set of 30 pulls from a brand new Bosch piece of kit which had a defective motor. And the spot weld is on its way from Germany.

How much did you budget for in materials for your first battery? Mine is looking like 180 euro so far, but a second battery should be around half that..

I don't budget, if I want it I buy it.
I wanted to learn how to repair them fault find them for the future as battery prices even for medicre cells aren't heap.
Things like nickel strip,bms,kapton tap etc etc I buy from China on Aliexpress a very good seller is Ann/Annbattery the nickle is pure and not steel plated.

Thats good to know. I'll be building two batteries for bikes of my own and I've been tasked to build a wall brick for my neighbours solar system next year. I guess the bike batteries will be good practice. He's an electrical engineer but he doesn't know one end of a soldering iron from the other. I am genuinely askance at the low uptake of solar in the south of France as we probably have about 300 good days of sunshine here...

[hemo]

Don't solder lithium as the heat time/duration of iron tip on cells is too long and will cause damage, heat is a batteries worst enemy.

[The utility cyclist]

Thanks for the link! I have ordered a set of 30 pulls from a brand new Bosch piece of kit which had a defective motor. And the spot weld is on its way from Germany.

How much did you budget for in materials for your first battery? Mine is looking like 180 euro so far, but a second battery should be around half that..

I don't budget, if I want it I buy it.
I wanted to learn how to repair them fault find them for the future as battery prices even for medicre cells aren't heap.
Things like nickel strip,bms,kapton tap etc etc I buy from China on Aliexpress a very good seller is Ann/Annbattery the nickle is pure and not steel plated.

And yet you budgeted by buying from China, seems at odds with your statement?

[thelawnet]

Thanks for the link! I have ordered a set of 30 pulls from a brand new Bosch piece of kit which had a defective motor. And the spot weld is on its way from Germany.

How much did you budget for in materials for your first battery? Mine is looking like 180 euro so far, but a second battery should be around half that..

I don't budget, if I want it I buy it.
I wanted to learn how to repair them fault find them for the future as battery prices even for medicre cells aren't heap.
Things like nickel strip,bms,kapton tap etc etc I buy from China on Aliexpress a very good seller is Ann/Annbattery the nickle is pure and not steel plated.

And yet you budgeted by buying from China, seems at odds with your statement?

budgeting is setting a limit. it is not the same thing as buying things as cheaply as possible.

(p.s. can't imagine any of that stuff is made in the West, so not buying it from China is a bit daft.)

[The utility cyclist]

I don't budget, if I want it I buy it.
I wanted to learn how to repair them fault find them for the future as battery prices even for medicre cells aren't heap.
Things like nickel strip,bms,kapton tap etc etc I buy from China on Aliexpress a very good seller is Ann/Annbattery the nickle is pure and not steel plated.

And yet you budgeted by buying from China, seems at odds with your statement?

budgeting is setting a limit. it is not the same thing as buying things as cheaply as possible.

(p.s. can't imagine any of that stuff is made in the West, so not buying it from China is a bit daft.)

I disagree, an outright statement saying I don't budget means there are no limits/caps as to cost/quality. The person writing that then goes and buys the product from China, which as we all know is done because it's very often cheaper to buy there than elsewhere. Which makes a bit of a mockery of saying "I don't budget, if I want it I buy it"
You can buy anything from elsewhere, you do not have to buy in china, it's disingenuous to say you can't, it often costs more, but then if you don't budget why would you buy from China and then brag about your deep pockets on social media?

[thelawnet]

And yet you budgeted by buying from China, seems at odds with your statement?

budgeting is setting a limit. it is not the same thing as buying things as cheaply as possible.

(p.s. can't imagine any of that stuff is made in the West, so not buying it from China is a bit daft.)

I disagree, an outright statement saying I don't budget means there are no limits/caps as to cost/quality. The person writing that then goes and buys the product from China, which as we all know is done because it's very often cheaper to buy there than elsewhere. Which makes a bit of a mockery of saying "I don't budget, if I want it I buy it"
You can buy anything from elsewhere, you do not have to buy in china, it's disingenuous to say you can't, it often costs more, but then if you don't budget why would you buy from China and then brag about your deep pockets on social media?

You are missing the point again. It's not about 'deep pockets', it's simply not imposing an arbitrary price limit on a project. 'Not having a budget' is not the same thing as having 'unlimited funds'.

[hemo]

Thanks for the link! I have ordered a set of 30 pulls from a brand new Bosch piece of kit which had a defective motor. And the spot weld is on its way from Germany.

How much did you budget for in materials for your first battery? Mine is looking like 180 euro so far, but a second battery should be around half that..

I don't budget, if I want it I buy it.
I wanted to learn how to repair them fault find them for the future as battery prices even for medicre cells aren't heap.
Things like nickel strip,bms,kapton tap etc etc I buy from China on Aliexpress a very good seller is Ann/Annbattery the nickle is pure and not steel plated.

And yet you budgeted by buying from China, seems at odds with your statement?

Buying from China not because of budget but reasons of choice from reliable sellers selling what I need and to the spec's that I need. EU/UK sellers selling same stuff but with inflated mark ups for which I refuse to pay just to swell their coffers for the same item. Nearly all the consumables are China made a lot of tech now comes out of China /Taiwan, the choice is bewildering. I see the same products on Ebay and Amazon at greatly inflated prices which on sellers need to do to make money.

[gxaustin]

Two people in my club have opted for the CyTronex add on motor/battery. The motor is in the front wheel and the battery is positioned on one of the water bottle mounts. It has the appearance of a fat water bottle. So far I have heard good reports. I think it costs about £1,000. Weight is under 4kg.