Low battery range

[John Cee]

I've had a Wisper torque since September last year. The battery range has always been considerably shorter than I expected, and by earlier this year I was only getting a range of about 12 miles. Wisper were very good about this and sent me a replacement battery without question. However, this was only a slight improvement from the old one. and for the last couple of weeks the new battery has been discharging down to about 2/5 bars on the display then going into what i believe is known as "LVC" - shutting down when extra power is needed to go up a hill. It seems unlikely that I've had 2 duff batteries, so is there anything else this can be other than a battery fault? I always follow recommended guidelines for battery care, i.e. charge every evening, never leave it uncharged etc.
I want to stress that this isn't a criticism of the manufacturers. They are happy to look into this and I've arranged to return it in the next few days. I'm just asking out of my own curiosity, really, as I like to know how things work.
Cheers
John

 

[Deleted member 4366]

There are some conditions that cause the motor to draw a lot of current from the battery, but you'd need a wattmeter to see them. The wattmeter would also show the actual capacity of the battery.

You can buy one from EBay for about £8, but you have to solder on connectors that match your existing battery connections so that you can plug it in or take it out.

As a temporary measure you can fit the controller side cover loosely and run the wires out to the wattmeter strapped to the bottom of the battery.

One last easy check that you can do is charge up the battery, then measure the voltage on the terminals as soon as you disconnect it from the charger.