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The eBike thread

unkel

A quick look seems that this doesn't really seem to fit in the cycling forum. So starting a thread here about all things eBike

I'll get the ball rolling. I have zero experience with eBikes. But I was going to build myself a battery anyway, for various reasons (like in bringing with me in my EV as a "petrol can")

I'm going to buy a solderless kit to make the battery (with 18650 cells I have removed from dead / old laptop batteries). This kit cah handle 20A max, and I would like the battery pack to produce 1kW constant. P=V*I so 1000W = 50V * 20A

This dictates that my battery needs to be nominal 48V (was thinking of making a 24V battery pack, but that won't be able to charge my car)

A quick browse on eBay and Amazon shows that you could buy a powerful 1000W bike conversion kit with everything needed except the battery for about GBP120 (a bit more from Amazon but peace of mind)

What to buy though, front wheel or rear wheel kit? Pros and cons? Any other advice?

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unkel

SCOL wrote: »

I like the idea of making my own battery, could I make a better battery for less money ?

Time for a bit of YT. See if this is something you would be interested in. Start with Micah Toll. This is the easiest way, using his Vruzend kit (no soldering / welding)

https://www.youtube.com/watch?v=rylbFnTgFI8

Not cheap though as the kit is expensive. But you get the idea. You can buy chargers on eBay from about a fiver including shipping.

SCOL

I'm thinking just to get started I might just buy a battery so would the motor and controller be able to handle either one ?

what's my best option there seem to be about €100 in the difference.
48v 13ah 750w
52v 13ah 1200w

Joe1919

SCOL wrote: »

EU 48V 13Ah lithium ion silver fish electrical ebike battery fits 750W motor for $220
this comes with a charger ?
I like the idea of making my own battery, could I make a better battery for less money ?
and also I would need to buy a charger ?

The silver fish battery slides down on a rail. It was really designed for older ebikes and usually went between the seat tube and the rear wheel/mudguard.

Pswpower have a good selection of 48V 'Hairon' batteries with chargers from 217 to 365 dollars. Be sure to get 48v.
http://www.pswpower.com/ven.php?cargo-s210052

[Deleted User]

You could use hobby king LiPo or LiFeP04, LiFeP04 isn't really suited for ebike use as it's bulky and heavy.

With LiPo you can make a cheap battery that can pull mega amps if you wish and charge at high amps.

Use 30 Amp "genuine" anderson connectors, there are a lot of fakes. I have a crimp tool also, dead handy. The 30 Amp andersons act as very convenient fuses should you cause a short by accident,. they vaporise in your hand.

LiPo poses obvious risks if abused they can go up in a ball of fire but never happened me, never store/charge in the house unattended.

You can use the LiFeP04 batteries also, you got to manage it yourself as there is no BMS so you need to watch that the cell voltages don't go too low or they could be damaged and that can become dangerous.

A BMS has it's own risks, especially for DIY use as it can cause catastrophic failure to the battery if it should fail.

The downside of course in the beginning is that you need an R.C battery charger to balance the cells and make sure they're not overcharged + you need to buy an external power supply for the charger.

unkel

Deleted User wrote: »

With LiPo you can make a cheap battery

Hardly. The cheapest way to do this would be with 2 * 5Ah 7S packs for USD70 each. This will give you a 5Ah battery (tiny, just for a very small local trip) for USD140. Plus expensive balance charger and charger power supply.

Using 2 7S hooverboard batteries you get a 6Ah battery for €50 and a charger would be about €10

For a novice who doesn't want to get involved in the sparky world of batteries (see what I did there?), the pswpower route is probably the safest...

[Deleted User]

You can find better much cheaper. lol. Don't have to go for anything over 20C LiPo,

The Hoverboard battery is fine if you want to have poor acceleration lol

unkel

Deleted User wrote: »

The Hoverboard battery is fine if you want to have poor acceleration lol

Nonsense.

Acceleration is determined by torque of the motor (nothing you can do about that) and the power applied to the motor

Max power applied to the motor is voltage of the battery * max amps of your controller.

It has nothing to do with the max amps your battery can discharge at (very high for lipo). Power is only restricted if the BMS prevents those max amps to be discharged from the battery. Which doesn't happen with the hoverboard batteries (and yes I know it's not good for the life expectancy of an 18650 cell to discharge it at 3C

)

[Deleted User]

unkel wrote: »

Nonsense.

Acceleration is determined by torque of the motor (nothing you can do about that) and the power applied to the motor

Max power applied to the motor is voltage of the battery * max amps of your controller.

It has nothing to do with the max amps your battery can discharge at (very high for lipo). Power is only restricted if the BMS prevents those max amps to be discharged from the battery. Which doesn't happen with the hoverboard batteries (and yes I know it's not good for the life expectancy of an 18650 cell to discharge it at 3C )

Torque of the motor + amps give torque.

Turn down the amps you turn down the torque, why do you think people modd controllers for more current which = amps ? why do you think I suggested adding a dab of solder to the shunt in the controller ? to allow more current for more torque.

add voltage and you go faster Lover voltage and you go slower but overall current x voltage gives watts.

More amps require a battery capable of supplying the power.

If you had a controller and were able to adjust it via software you can also see that limiting current limits acceleration, speed can be limited by voltage or software.

unkel

Deleted User wrote: »

More amps require a battery capable of supplying the power.

The controller in the BBS02 motor has max 30A. The BMS of the hoverboard batteries lets the batteries discharge at 30A (that's 2.5C in a 12Ah pack like the one I use). So the acceleration with the hoverboard battery is not slower than with any other battery. Which is what you claimed. You were wrong.

[Deleted User]

Ah you see I wasn't thinking about the BBS02

I'd love to see how long the battery lasts at that current lol.

unkel

I rode the bollox out of the bike last Sunday during the worst of storm Ciara. Still lasted the guts of 20km. Or do you mean number of charging cycles? I don't give a sh1t tbh. If I get a few hundred cycles out of it (several years use for me taking the bike out maybe once or twice a week), that's fine for the €100 I spent on this pack

[Deleted User]

unkel wrote: »

I rode the bollox out of the bike last Sunday during the worst of storm Ciara. Still lasted the guts of 20km. Or do you mean number of charging cycles? I don't give a sh1t tbh. If I get a few hundred cycles out of it (several years use for me taking the bike out maybe once or twice a week), that's fine for the €100 I spent on this pack

Well at least you're having fun.

SCOL

unkel wrote: »

I rode the bollox out of the bike last Sunday during the worst of storm Ciara. Still lasted the guts of 20km. Or do you mean number of charging cycles? I don't give a sh1t tbh. If I get a few hundred cycles out of it (several years use for me taking the bike out maybe once or twice a week), that's fine for the €100 I spent on this pack

Do you have a link for these ? I assume I solder the wires together.

unkel

I usually crimp them in series and then I parallel connect them with XT60 parallel connectors (couple dollars from AliExpress / eBay). The batteries I used for my bike are 24V (29.4V) 6Ah packs from Aliexpress. About USD28 and free shipping, but make sure the seller ships them separately, otherwise you can be hit for VAT / customs charges

Beware though. This route is not for everyone. The pswpower battery is all done up and will probably last longer than these hover board batteries. For not exorbitant money.

SCOL

unkel wrote: »

I usually crimp them in series and then I parallel connect them with XT60 parallel connectors (couple dollars from AliExpress / eBay). The batteries I used for my bike are 24V (29.4V) 6Ah packs from Aliexpress. About USD28 and free shipping, but make sure the seller ships them separately, otherwise you can be hit for VAT / customs charges

Beware though. This route is not for everyone. The pswpower battery is all done up and will probably last longer than these hover board batteries. For not exorbitant money.

OK, I think I fould them on Aliexpress they are $28. So I how many of these do I need ??

100% High capacity 24V 6Ah 18650 Battery li-ion battery pack 29.4v 6000mah Electric bicycle moped /Li-ion battery

unkel

Bought another faulty 1000W electric scooter. As expected, turns out the lead acid batteries (*4!) were dead. Replaced them with one of my 58.8V packs and the thing is flying again

So might sell it with both my double packs, which means I will have to buy something else. Would consider spending a bit more to have a higher discharge rate pack, was still considering lipo as per Mad_Lad's advice, but came across this:

Andy Kirby says: don't use lipo

https://www.youtube.com/watch?v=u2cgm6ibecY

SCOL wrote: »

OK, I think I fould them on Aliexpress they are $28. So I how many of these do I need ??

Depends on what you want to do and how much you want to spend. If you take it handy with the throttle (or don't use it at all), use mostly the lower levels of pedal assist and don't need much range, 2 will do. If you need more, get 4

Utter Consternation

I was out on the ebike in the pissings of rain last Friday. I switched it on this morning and was wheeling it around the side of the house when it took off on it's own accord (it has a rear hub motor). I had to turn it upside to stop it running off on me. It appears the freewheel is sticking a little (after the rain) and rotating the pedals which in turn activates the PAS. The chain also needs a good oiling after last friday.

Will firing a bit of oil on the chain solve all this problem?

[Deleted User]

unkel wrote: »

Andy Kirby says: don't use lipo

Well I suppose if Kirby says don't use LiPo then don't use LiPo, what would Mad_Lad know about LiPo I suppose ? Not like he built LiPo packs or anything !

SlowBlowin

I must admit that, although I watch his videos, I do think Andy Kirby is a bit of a knob. He reacts in childish ways, and technically he makes mistakes, especially with his renewable systems. Basically if he does something, and it works, he thinks thats the best way if doing it, but all in all hes an interesting watch..

SCOL

48V 14.5Ah Hairon the interior battery SAMSUNG INR18650-29E ebike battery fit 48V 750W/ 1000W - $300
48V 13h Hairon the interior battery LG LGEBM261865 18650 ebike battery pack fit 48V 750W/ 1000W - $275
48V 13 Ah Hairon ebike electrical battery pack with 54.6V 2A charger can working on 750W motor - $240

I need to get a battery sorted out. I'm thinking of buying a battery and when I get it up and running go and buy the packs and make one up and see if there is a performance difference.

Is there much of a difference between these ?

unkel

Deleted User wrote: »

Well I suppose if Kirby says don't use LiPo then don't use LiPo, what would Mad_Lad know about LiPo I suppose ? Not like he built LiPo packs or anything !

Well, we can have a discussion here about using LiPo vs 18650 based battery packs.

The major benefit of lipo is that it can be charged / discharged at much higher rates than lithium ion. This is vital if you need a very high power application and it doesn't matter that it can only work for a very short time at max power. But what does matter is the weight of the pack. It is clear this would be a major benefit for say a remote control helicopter.

Is this a major benefit for an eBike though?

[Deleted User]

unkel wrote: »

Well, we can have a discussion here about using LiPo vs 18650 based battery packs.

The major benefit of lipo is that it can be charged / discharged at much higher rates than lithium ion. This is vital if you need a very high power application and it doesn't matter that it can only work for a very short time at max power. But what does matter is the weight of the pack. It is clear this would be a major benefit for say a remote control helicopter.

Is this a major benefit for an eBike though?

Depends on your requirements, if like me at the time and you needed high power from a very small pack then yes absolutely it does matter for an ebike.

It's not just about running power for a short time it's about having the power when you need it.

For a long time I was running just 5 Ah at around 60 volts, that gave me about 300 watt hrs of storage, this was plenty for up to 50 Km even with decent hills because I peddled a lot and lost a tonne of weight in the process, if only I had the time to do that again lol. My Bosch Ebike had 400 Watt hrs of storage new, 36v 14 ah.

Small pack for cycling that could give me the amps when needed, for instance, my old bike could do 60 Km/hr so if I was out on a nice summers day and I say a black sky coming or hear a clap of Thunder, I'd yank that throttle to get me home.

or a hill I needed to get up quickly, or my legs were tired and I wanted to get up a hill quickly without peddling.

It's super easy to make packs out of LiPo bricks, charging is the only issue if you want to call it that, RC charger and Power Supply and the pack has to be charged in Parallel and then connected back in series/parallel for the bike but to be honest that didn't bug me at all.

If you have a BBS02 or BBSHD then this makes it easier to find a suitable battery these days if you really must have a BMS which is probably good for some people who might find it difficult to monitor cell voltages and the likes.

As I type this I have em3ev.com site open looking at his batteries and he has a LG HG2: ~ 44A Continuous, 55A Max Burst Current, voltage is 52 volts which would be more than enough to run my old MAC 8T motor at 50 Km/hr and still climb plenty of decent hills with no issue this would give me 2.2 Kw of power in a battery that is small and reasonable weight.

It costs 465 Euro's before shipping and import charges though which would make it probably 100 Euro's more expensive ?

I know Paul's batteries are pricey but they're built to the best quality and his reputation on endless sphere is excellent so I would pay more to have a pack of known good quality compared to a battery of unknown quality that might not even have the cells specified. Dodgy batteries are all too common.

He does have cheaper batteries of course with less current capability.

unkel

Deleted User wrote: »

Depends on your requirements, if like me at the time and you needed high power from a very small pack then yes absolutely it does matter for an ebike.

Maybe that explains it? A 52V battery pack made of 18650 cells that you could draw a peak of 30A out of (without doing it harm) might have been big, so heavy and more importantly, extremely expensive the guts of 10 years ago? So lipo would have been a good alternative?

These days batteries are so cheap that you need not worry about them much. I draw 30A out of a EUR50 52V nominal pack regularly. If that kills the battery within a year, so be it, I'll just buy another one.

Joe1919

SCOL wrote: »

48V 14.5Ah Hairon the interior battery SAMSUNG INR18650-29E ebike battery fit 48V 750W/ 1000W - $300
48V 13h Hairon the interior battery LG LGEBM261865 18650 ebike battery pack fit 48V 750W/ 1000W - $275
48V 13 Ah Hairon ebike electrical battery pack with 54.6V 2A charger can working on 750W motor - $240

I need to get a battery sorted out. I'm thinking of buying a battery and when I get it up and running go and buy the packs and make one up and see if there is a performance difference.

Is there much of a difference between these ?

Here is my opinion and reasons.
The three batteries look similar in so far as they all have 65 cells. The big difference is in the cells. The last battery (for $240) has generic china unbranded cells, so I would not buy this battery (unless it was far cheaper).
That leaves us with a choice between Samsung 2.9 cells or Lg 2.6 cells. Both are good quality brands. The Samsung has a little extra capacity, so I would be inclined to spend the extra $25 for the extra 11% capacity.

John Hutton

So I most definitely have caught the ebike bug!!

Absolutely loving my bafang middrive touring bike conversion. Super powerful, great range, works well. Am using this for long spins and will do some mini tours. I have a lot of other expensive components on this bike and having completely restored it from an initial dreadful condition I've really fallen in love with it - this means I can't use it everyday!

My everyday bike is a Brompton. As previously said I'm looking into ways to electrify this but tbh it's probably not necessary.

What I would like to do is get a donor bike which has a very upright cycling position (touring bike has drop bars and Brompton has a sporty position too) and electrify it.

On this set up I'm going to stick with mid drive, but will go with a small battery as I don't plan on going more than 15 or 20 km a go. I'll be making it a bit more discrete as I'll be using it for popping to the shops etc and may be locked up here and there for a while, so the intent is to keep it cheap. I'm also going for 100% legal for public road use also.

I'm thinking of using
The tsdz2 as it is torque sensing
https://www.google.com/url?sa=t&source=web&rct=j&url=https://ebikechoices.com/tongsheng-tsdz2-review/&ved=2ahUKEwjSr_nBxt3nAhXkuXEKHehJBOIQFjAEegQIARAB&usg=AOvVaw2fGXwXtrPkDee4KTJpJjyX&cshid=1582113181136

Anyone use this motor and have any opinions?

Any suggestions of donor type bikes to keep an eye out for would be appreciated

John Hutton

John Hutton wrote: »

So I most definitely have caught the ebike bug!!

Absolutely loving my bafang middrive touring bike conversion. Super powerful, great range, works well. Am using this for long spins and will do some mini tours. I have a lot of other expensive components on this bike and having completely restored it from an initial dreadful condition I've really fallen in love with it - this means I can't use it everyday!

My everyday bike is a Brompton. As previously said I'm looking into ways to electrify this but tbh it's probably not necessary.

What I would like to do is get a donor bike which has a very upright cycling position (touring bike has drop bars and Brompton has a sporty position too) and electrify it.

On this set up I'm going to stick with mid drive, but will go with a small battery as I don't plan on going more than 15 or 20 km a go. I'll be making it a bit more discrete as I'll be using it for popping to the shops etc and may be locked up here and there for a while, so the intent is to keep it cheap. I'm also going for 100% legal for public road use also.

I'm thinking of using
The tsdz2 as it is torque sensing
https://www.google.com/url?sa=t&source=web&rct=j&url=https://ebikechoices.com/tongsheng-tsdz2-review/&ved=2ahUKEwjSr_nBxt3nAhXkuXEKHehJBOIQFjAEegQIARAB&usg=AOvVaw2fGXwXtrPkDee4KTJpJjyX&cshid=1582113181136

Anyone use this motor and have any opinions?

Any suggestions of donor type bikes to keep an eye out for would be appreciated

Should say a step through bike would be ok either as the auld lad would be able to use it then

unkel

For fully legal, why not just get a front 250W wheel? And a speed sensor if that doesn't come with the kit? Cheapest option and easiest to implement.

John Hutton

unkel wrote: »

For fully legal, why not just get a front 250W wheel? And a speed sensor if that doesn't come with the kit? Cheapest option and easiest to implement.

There are some nasty hills nearby, figured mid drive would be more efficient by using the bikes gears, and would pedal easier if battery ran out.

unkel

Geared hub drive pedals even easier than mid drive if battery runs out. Will even bring you home if the chain breaks

But you're right, mid drive is more efficient in a low gear up a steep hill. Is efficiency that important? For the cheaper price of the wheel kit, you can install a bigger battery and still have money left over. Less maintenance too. Nothing to go wrong with a hub motor if gently used (max 250W)

John Hutton

unkel wrote: »

Geared hub drive pedals even easier than mid drive if battery runs out. Will even bring you home if the chain breaks

But you're right, mid drive is more efficient in a low gear up a steep hill. Is efficiency that important? For the cheaper price of the wheel kit, you can install a bigger battery and still have money left over. Less maintenance too. Nothing to go wrong with a hub motor if gently used (max 250W)

Can you get hubs with integrated controllers?