The design and development of a prototype supercapacitor
powered electric bicycle (E-bike) is presented. An
existing general-purpose bicycle was retro-fitted with a brushed
DC motor driving the front wheel, a super-cap bank capable of
storing 74 kJ, and a bi-directional motor driver for acceleration
and regenerative braking. It was envisaged that the designed
E-bike would fulfil the role of a campus commuter, whereby
members of the university’s community could utilise such Ebikes
to traverse a large campus. Consequently, the range of the
E-bike was not as important as the rapid and frequent charge
cycling requirements, hence the benefits of using super-capacitors
as an energy storage medium was exploited. For the design of
the E-bike, an 80 kg cyclist was assumed. However, the developed
prototype was tested with a 55 kg cyclist and demonstrated a satisfactory
range (pedalling-free) and top speed of approximately
1100 m and 23 km/h respectively. Two weaknesses of the design
that need future consideration are the unbalanced charging of the
series-connected super-capacitors and the inadequate response
time of passive thermal fuses under short-circuit conditions of
the super-cap bank