Dual Batteries
Hi Conal
We have found that our 36v 14a lithium polymer does the trick already without the need for more than one battery although as Wai Wan says we could easily ad another battery in parallel giving us a 1032ah model.
Our batteries have recently been tweaked and we have just finished REAL ROAD TESTS in shanghai, as against rolling road tests which are always massively inaccurate and err towards giving ebike ranges a huge boost! The results we seriously impressive. An example;
Rider: 77kg (12 stone)
Air temperature: 10 to 12 degrees
Wind: 2-3
Road surface: Good, Dry
Rout: Circuit, Flat
Maintained speed: 25kph
Mode: Throttle Only
Battery voltage prior to tests: 41.5v
Battery voltage after tests: 34.4v
Range
Test 1
Braking 14 times
65km (39 miles)
Test 2
Braking 22 times
59 km (35 miles)
These tests were with throttle only, we then tested with pedal assist, the ranges varied between 71 km (43 miles) and 118km (71 miles) depending on the amount of assistance the rider gave to the motor.
The 905xs will be heavier because of the extra motor but on single motor use we would expect similar results and with both motors operating we expect to see up to a 30% drop depending on conditions.
Ranges are always difficult to work out so much depends on variables such as;
Tyres
Tyre pressure
Wind resistance
Rider weight
Braking
Air temperature
Road conditions
Hill climbs
However I believe the tests carried out this week were as fair as we could get.
All the best David