Testing Lithium 36v 10ah battery

[JuicyBike]

Sorry could you advise me how you would test them please. Thanks

We have a rig that drains a fully charged battery to cut-off voltage at 10amps current. If that process takes 60 minutes then we have a 10ah battery.

 

[robert1976]

Power consumption varies with speed to the cube, hence very sensitive to headwinds. The next factor is motor type. Hub motors tend to give you more miles - about 30miles-33 miles for a 36V10AH battery, crank drives about 10%-20% less because most people with CD motors tend to ride 20% faster, direct drive motors are worst for consumption because of very low motor efficiency at low speed, frequent start/stop at traffic lights in town can easily half your miles. The next factor is the maximum continuous output of the battery. If this factor is low, your battery will sag heavily when climbing hills, reducing range due to Peukert effect.
Tell us what motor/controller you have, we can advise what is reasonable to expect.
How to test:
Your battery is at least functional, so the main reason for testing is to find out if the capacity is as advertised and if the cells are well balanced. The simplest method that you can do at home is to get yourself an energy meter, something like this:
http://www.ebay.co.uk/itm/Status-Plug-In-Energy-Meter-kWh-Electricity-Monitor-Consumption-Usage-Analyzer-/141833338442
Charge your battery to full, reset your trip meter.
Ride until the battery is pretty flat.
Let's say you ride 15 miles.
Plug your charger to the energy meter and plug the energy meter to the wall socket.
Charge up the battery to full.
Check the amount of electricity used.
On a good bike, one would expect to see 5AH used. The power consumption shown onyour meter should be about 200WH.
Now measure the voltage of your battery.
When it's 100% full, it should be 41.5V, when it's very flat, 31.5V, so you should expect to see 36V.
You get the idea.

yep thanks. the motor regenerates type quite big and will not exceed 20 mph on a 14% decline. appreciate the time spent typing.

 

[flecc]

funride

Looking at that bike, shown on this link, the in-frame lithium battery is obviously very small physically. That, plus this style of bike and you saying not much pedal assist from you makes me think that 10 miles is quite possibly right.
.

 

[robert1976]

Looking at that bike, shown on this link, the in-frame lithium battery is obviously very small physically. That, plus this style of bike and you saying not much pedal assist from you makes me think that 10 miles is quite possibly right.
.

Looking at that bike, shown on this link, the in-frame lithium battery is obviously very small physically. That, plus this style of bike and you saying not much pedal assist from you makes me think that 10 miles is quite possibly right.
.

http://www.pedelecs.co.uk/forum/threads/fun2ride.22452/ my bike

Current battery is 240mm * 81mm * 65mm

 

[flecc]

You posted funride, hence my link, but you have the fun2ride. Still my advice is the same, I see you got around 12 miles originally so 10 miles after some usage is quite possible. Although listed as 250 watts for legal reasons, those moped style ones are more usually far more than that, sold in China they are usually said to be around 700 watts true rating

That plus the high 38 kilo weight, hills and not much assistance from you will result in a low range from a 36 volt 10 Ah battery.
.

 

[robert1976]

You posted funride, hence my link, but you have the fun2ride. Still my advice is the same, I see you got around 12 miles originally so 10 miles after some usage is quite possible. Although listed as 250 watts for legal reasons, those moped style ones are more usually far more than that, sold in China they are usually said to be around 700 watts true rating

That plus the high 38 kilo weight, hills and not much assistance from you will result in a low range from a 36 volt 10 Ah battery.
.

Its hard to assist as you can only peddle to 10 MPH after that being a single geared bike its impossible to peddle faster.

 

[robert1976]

This is the battery I just bought and its even worse than one I have. the volts just drop off

http://www.ebay.co.uk/itm/252143857710?_trksid=p2060353.m1438.l2649&ssPageName=STRK:MEBIDX:IT

 

[Alan Quay]

I agree with Flecc. 12 miles is good going.

 

[flecc]

Its hard to assist as you can only peddle to 10 MPH after that being a single geared bike its impossible to peddle faster.

I know Robert, that's the trouble with these moped style machines, they really aren't designed to be pedalled all the time. In China where they are very popular, they never pedal, just ride on the throttle all the time.

Also, in China they usually have SLA batteries instead of lithium and typically only ride short distances in towns.
.

 

[anotherkiwi]

10ah should be good for about 20 miles if:

You weigh less than about 80 kilos
You put in a bit of effort yourself
You don't have massive hills/headwinds.
You have a 250w (15a) motor

An example of range with a 10.4 A bottle battery with Samsung cells

77-78 kg
supply quite a bit of effort
Have a very big hill on my usual route and wind from time to time
250W (15A) motor

Yesterday when I left home there was 26 km on the odo and when I got home 69 km and after recovery from battery sag 35.4 Volts in the battery. That is about 43 miles on a charge - I think the secret is point 2 on the above list. The ride was about 40 km of going up and down hills and the rest was as flat as a pancake. If you ride on flattish roads using only assistance levels 1 and 2 you can get 100 km - over 60 miles from a 10 A battery, I have done it.

This shows the difference between a bike and a scooter. My bike weighs 20.5 kg with the battery.

 

[robert1976]

Ive been qouted £10 to have tested an 5 hrs test time. For my 36v 10ah battery. Have to get train and have day out. Really dont think thsts going to happen lol

 

[robert1976]

I agree with Flecc. 12 miles is good going.

hopefully ill have no problem now as joined batteries 36 volt 20 ah.

 

[robert1976]

Battery's joined was pleasant short ride today. top speed hit quick and maintained on flat. only did 2 miles those

 

[robert1976]

Did 11 miles today hardly any assist. Great ride. average 15.4 mph going out at 5.6 miles. Home I averaged 13.7 mph At 5.3 miles took different route.

 

[robert1976]

did the full 12 miles and plenty off poke left in her. very happy with that. Just the charge time is like for ever now lol