48v left- what range left ?

[Peter.Bridge]

I went for a ride this morning and my battery voltage (measured with multimeter) fell from 54.6 to 48.1 and I travelled 31 miles. If I travelled the same route at the same level of assist, what mileage range would I have left before the battery was "empty" ?

 

[Nealh]

Typically one can expect LVC cut out at 42 - 43v, so possibly 20 - 25 miles though at a push one may cover the same mileage. However for that type of journey it doesn't pay not to recharge to full again.

 

[matthewslack]

The 'nominal battery voltage' is not too far off half charge, so half a battery left. The second half will last until the first time a hill drags voltage down to low voltage cutoff, so in flat country you might get another 30 miles, in hilly lands maybe only 15.

 

[harrys]

Matthew has it right. Voltage sag will cause the bike to shut off when the nominal battery voltage is 42-44 volts, above the 40V cutoff you may expect. It's always there, and if you have the means to view it on your meter when riding, you can see the difference between being under power and not,

A brief hill encounter might drop the voltage 3 volts to the bike. At full charge, no big deal, but when you're at 30%, or 43 volts on the battery, the bike will shut off, Sag is nonlinear too, so what might be 3V at full charge is higher at half charge, If you have no such hills, or compensate by pedallng harder, you might get another 30 miles, 20 miles for sure,

 

[sjpt]

It's when you are tired and nearly out of your own charge and hit a hill near the end of a ride that you need the motor help most. Batteries are very empathetic; it's exactly at that point that the battery sag hits in and cuts out the motor.

 

[Peter.Bridge]

It's when you are tired and nearly out of your own charge and hit a hill near the end of a ride that you need the motor help most. Batteries are very empathetic; it's exactly at that point that the battery sag hits in and cuts out the motor.

Thanks all, I'd not thought about steep hill battery sag taking you below the minimum voltage cut out. I'll make sure all the hills are on the first half of any long rides ! This was more 'flattish' than a lot of my rides, but even so , it says my elevation gain (on a circular route) was 1300 ft
Also, I noticed needing one level higher assist on long rides when I get into the second half of my battery range. I think this is because it's running at a lower voltage so less oomph.

 

[saneagle]

I went for a ride this morning and my battery voltage (measured with multimeter) fell from 54.6 to 48.1 and I travelled 31 miles. If I travelled the same route at the same level of assist, what mileage range would I have left before the battery was "empty" ?

Approximately 15 miles. . Your battery was about 60% to 65% depleted. You get less power as the battery runs down so you either have to pedal harder or turn the power setting up if you have one.