24v Battery Replacement Options

[Smilerbatten]

Hi All,

I have a 24v e-bike made by Micro Scooters who have since deprecated the bike and I can’t buy new batteries for.
the battery is a two wire 24v 4Amp 86.4wh battery, the brushless Controller is 24v max current 10Amp, rated current 5A
Wheel motor is 24v/250W

what is the best option to replace the battery?
I was thinking to use a power tool battery from a 24v range with one of those power wheel battery adapters but not sure those have been used for bikes?

any ideas what I can do?
I can post pictures if needed.

thank you.

 

[Peter.Bridge]

the battery is a two wire 24v 4Amp 86.4wh battery,

That's the smallest capacity ebike battery I've ever heard of !

Please post pictures

AliExpress has 24v batteries and battery mounts, choose the seller carefully

 

[Smilerbatten]

Green works makes a 24v 4a battery with charger for £79.99 and I would just need to fit the power wheel adapter to the bike somehow.

would this work?
This is the battery: https://www.ebay.co.uk/itm/335735013300?

this is the power wheel adapter

Adapter for 24V greenworks or creabest battery 12 gauge power output | eBay

Compatible with greenworks and creabest models: 29852, 29722, BAG709, and BAG711.

www.ebay.co.uk

Could this work?

 

[Smilerbatten]

 

[saneagle]

Hi All,

I have a 24v e-bike made by Micro Scooters who have since deprecated the bike and I can’t buy new batteries for.
the battery is a two wire 24v 4Amp 86.4wh battery, the brushless Controller is 24v max current 10Amp, rated current 5A
Wheel motor is 24v/250W

what is the best option to replace the battery?
I was thinking to use a power tool battery from a 24v range with one of those power wheel battery adapters but not sure those have been used for bikes?

any ideas what I can do?
I can post pictures if needed.

thank you.

Are you happy with that low amount of power? It's the lowest I've ever heard of in 14 years on this forum. There's plenty you can do to get more power if you want it.

 

[Smilerbatten]

Haha! Yes more power would be good but assume I would then need to change controllers, wheel motor etc. it’s only a foldable Brompton style bike I use for commuting on trains for around 6 miles. I just need a battery I don’t charge every day!!

This is the bike, battery is mounted on the handlebar: https://www.micro-scooters.co.uk/micro-pedal-assisted-electric-bike-black-6895

 

[Peter.Bridge]

Haha! Yes more power would be good but assume I would then need to change controllers, wheel motor etc. it’s only a foldable Brompton style bike I use for commuting on trains for around 6 miles. I just need a battery I don’t charge every day!!

This is the bike, battery is mounted on the handlebar: https://www.micro-scooters.co.uk/micro-pedal-assisted-electric-bike-black-6895

That's got all sorts of possibilities !

Looks like a standard connector to the rear hub motor wheel




So - you could just leave the existing controller and display and use a new 24V ebike battery - all sorts available - has your bike got rear rack fitting points ?

or possibly https://www.yosepower.co.uk/products/24v-36v10ah-frog-li-ion-e-bike-seat-tube-battery

or (I would do this) replace the battery, controller and display and change it to 36V

 

[saneagle]

Haha! Yes more power would be good but assume I would then need to change controllers, wheel motor etc. it’s only a foldable Brompton style bike I use for commuting on trains for around 6 miles. I just need a battery I don’t charge every day!!

This is the bike, battery is mounted on the handlebar: https://www.micro-scooters.co.uk/micro-pedal-assisted-electric-bike-black-6895

The reason the controller's power is so low is because it needs to limit the power from the very small battery. It's a normal motor, so it should be able to easily handle 36v and 15A, which would be double the power. The question is how much jiggery-pokery you're prepared to do to get that power.

Most 24v controller's can handle 36v, but it's not guaranteed. If you simply attached a 36v battery, you'd get a 30% increase in power. In the worst case that it blows, a standard replacement 36v one is only about £15 to £20, though you might have to do a bit of wiring and stick it in a bag somewhere. If you stick with your 24v controller, it won't cut off when the 36v battery is empty. The battery should have its own cut-off, but it's best not to rely on that, so you have to think about how to manage that, which would be no problem if you did short journeys and never ran the battery down that far.

Alternatively, if you decide to get a more powerful 24v battery, you could get a 15A controller too that would give you a 50% power increase.

Whether you want 36v or 24v, if you want small and lightweight, look for a hoverboard battery, like this one that can do 20A continuous. Some come in plastic cases.

Hoverboard Swegway Samsung High Power Battery - British Hoverboards

Specifications Hoverboard Battery Type: Samsung Cell Technology: Lithium-Ion Battery Voltage: Hoverboard battery 36v Capacity: 4.4Ah Cut-off voltage: 26V Maximum Voltage: 42V Structure: 10S2P & 10S1P Internal Cell Size: 18650 Lithium Ion Max. discharging current: 30amp Max Continuous Discharging...

britishhoverboard.co.uk

 

[Smilerbatten]

Thank you both for the replies:
I like the idea of upgrading to 36v with the yosepower seat mounted battery.
Would the 24v / 250W motor work with a 36v battery if i updagred the battery and controller?
Is this the controller I would need: https://www.ebay.co.uk/itm/387201940607?
as it has the same 9 PIN motor connector?

Thanks again.

 

[saneagle]

Thank you both for the replies:
I like the idea of upgrading to 36v with the yosepower seat mounted battery.
Would the 24v / 250W motor work with a 36v battery if i updagred the battery and controller?
Is this the controller I would need: https://www.ebay.co.uk/itm/387201940607?
as it has the same 9 PIN motor connector?

Thanks again.

Motors don't care about voltage. It just makes them spin a bit faster. All those type of motors can handle 650w from the battery fairly comfortably - more so in small wheels.

 

[Peter.Bridge]

Thank you both for the replies:
I like the idea of upgrading to 36v with the yosepower seat mounted battery.
Would the 24v / 250W motor work with a 36v battery if i updagred the battery and controller?
Is this the controller I would need: https://www.ebay.co.uk/itm/387201940607?
as it has the same 9 PIN motor connector?

Thanks again.

Do you have an existing display - how do you turn it on at the minute ? (usually displays and controllers are paired.)

There is usually a pedal sensor that goes into the controller. Sometimes there are cut offs from the brake levers so the power cuts out - I can't see them on yours

Ah here is the pedal sensor and the existing controller - @saneagle suggested that controller might work with a 36V battery

If not, I would be tempted to buy a matching controller and display and pedal assist sensor and they should all connect together without soldering

 

[Smilerbatten]

there is no current display! i just hook up the battery and turn the battery on for it to work.
There is a pedal sensor and thats it. the controller has only 3 wires out of it, 1 9 PIN cable for the motor, 1 x to the battery, 1 to the crank / pedal sensor. No display, no brake cutoff or any other cables.
So i guess the plan is to buy the yosepower 36v battery and just plug it in, or to also change the controller to one that can also work and that can give me a nice display as well!

Is that right?

 

[Peter.Bridge]

there is no current display! i just hook up the battery and turn the battery on for it to work.
There is a pedal sensor and thats it. the controller has only 3 wires out of it, 1 9 PIN cable for the motor, 1 x to the battery, 1 to the crank / pedal sensor. No display, no brake cutoff or any other cables.
So i guess the plan is to buy the yosepower 36v battery and just plug it in, or to also change the controller to one that can also work and that can give me a nice display as well!

Is that right?

Yep - If it was me, I would try a new battery with that controller, if that didn't work, then buy a matching controller/display/ pedal sensor

There is lots of options for 36V batteries - bag battery for lightest weight , rack battery if you have rack mounting points, seat post battery, bottle battery. Yosepower seem fine - but there are other options

36V Batteries

Professional manufacturer and seller of electric bike, electric bicycle batteries, ebike conversion kits. The same product with Amazon and lower price.

www.yosepower.co.uk

 

[saneagle]

Please let us know what you do and how you get on.

 

[Peter.Bridge]

One other thought I had was that if you have no display then I think you will get full power from the controller until you approach the assist cut off speed (25km/h). If you had a display, these typically have pedal assistance levels that you can set in the display to suit yourself. This will typically give you much more range

Also I have a slight worry, that with that controller, it will continue to try and draw power from a 36v battery when it is empty (voltage has fallen to 30V) and you are relying on the battery BMS to shut down and protect the battery. (which it should do) Which would be an argument for replacing the pedal sensor and controller with a matched new pedal sensor, 36v controller and display

This was the first one when I Googled, KT brand which is very good but can get cheaper

KT kunteng 24V 36V 48V 250W 500W 1000W Brushless DC Sine Wave sensor Controller | eBay

Find many great new & used options and get the best deals for KT kunteng 24V 36V 48V 250W 500W 1000W Brushless DC Sine Wave sensor Controller at the best online prices at eBay! Free delivery for many products.

www.ebay.co.uk

 

[Smilerbatten]

I am struggling to find a controller with this pedal assist connector. It’s a 6 pin connector. It comes directly out of the frame from the bottom bracket so trying to not replace it if possible!

this is the current battery connector that has 2 big connectors and then strangely enough has 4 very fine connectors that I have no idea what they are using for as this connects to a 2 pin battery terminal
This will go anyway if I get a new controller and battery combo, but I wanted to keep the pedal assist if possible.

 

[saneagle]

They're special for that bike and battery. Your controller might not work with a standard battery. It's best to budget for a new controller too and figure out how/where you're going to install it.

 

[thelarkbox]

Generic pas sensors tend to have 3 wire connections, and anything other than 2x hi-power connections to the battery is a red flag warning of superfluous battery communication features that in reality mainly just hamper the use of 3rd party batteries.

So the above suggestions for a KT controller and display would simply avoid any specialist (torque?) sensor searches and possible battery communication hurdles roadblocks.

Some folk have attested the KT controllers respond to pedal movement or the lack of it rapidly and brake cut off sensors are a redundant feature, I would suggest adding a couple of the stick on sensors designed for hydraulic brakes would be a worthwhile backup for a nominal extra cost (£5?)

When replacing a controller with a limited housing space measure the existing box and carefully note any critical dimensions so you can ensure any replacement will fit the void available.

 

[Nealh]

It is pretty much obvious (to us) that the battery connector is using extra comms hence the four small wires as well. It is indicative the system if not CANbus is using some handshaking between controller/battery and possibly the charger .
In doing so it ties one in to that manufacturer/brand meaning usually expensive replacements.

One has to weigh up the cost of a new battery /control system, all costing approx £300 - £400 dependant on the battery bought or puutying that money towardd a new bike.

A new good control system costing £70 - £100 would be a KT system which has the instant PAS control with no lag , the KT doesn't need the extra complication of brake sensors unless one of course wishes to use thumb speed switch (aka thumb throttle).

 

[Peter.Bridge]

@saneagle @Nealh @thelarkbox

So if the op bought a Yosepower 36v seatpost battery (£173) and KT controller, display, cable and pedal sensor

KT kunteng 24V 36V 48V 250W 500W 1000W Brushless DC Sine Wave sensor Controller | eBay

Fits Bafang 8FUN MXUS sengyi 250W sensor motor AKM 250W 350W sensor motor. Applicatoin: Max. 24V/36V or 36V/48V 250W. 36V/48V 500W. Fit bafang 8FUN MXUS sengyi AKM 500W sensor motor. 36V 1000W-1500W or 48V 1000W -1500W.

www.ebay.co.uk

£52.20 + 10.80 postage

That would potentially be a solution ? £236 total