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6 BATTERY CHARGING & MAINTENANCE
6.1 Battery overview
Our Lithium Ion Rechargeable 36V 11.5Ah 414Wh Flat Pack Battery using Panasonic cells weighs only 2.5
kg. Maximum discharge current is 15A continuous, 20A for 10 seconds and 35A for 5 seconds. Maximum
charge voltage is 42.5V.
The BMS (Battery Management System) technology protects packs from heat, voltage imbalance, under-
voltage and over-current. The BMS dramatically improves cycle life and prevents battery fires and
explosions.
6.2 Battery life
A batteries power is reflected in (Wh) Watt hours. The more Wh there are the greater the potential power
boost and likely range of the battery. Battery and electric bike manufacturers do tend to exaggerate when
giving mileage per battery charge calculations but through experience we can say that our batteries give a
minimum of 1 mile per 35Wh, this works out at 11.5 miles with our 11.5Ah flat pack 36V batteries.
Most manufacturers will give much higher mileage per charge figures than we have stated for a number of
reasons. Tests carried out in a laboratory are under controlled conditions of constant temperature and at a
constant discharge rate with each cycle being repeated immediately after the last one. Field-testing is
carried out using two wheeled electric bikes whilst the user is utilising pedal assist.
A three-wheeled cycle is always going to be less efficient than a two-wheeled bicycle as the batteries have
to work much harder to haul three wheels. The Viper battery has extra stress as it has to do all of the
work whereas power assisted handcycles and bicycle batteries generally have a much easier life.
Other factures that dilute the battery packs miles per charge are varying types of terrain, headwinds, hills,
rider weight, tire pressures, speed, temperature stopping/starting and more.
From the information above it can be seen that it is virtually impossible to give an accurate guide on
mileage per charge or an accurate guide to the number of cycles a battery can achieve. But as a general
rule our batteries should return 500-600 cycles.
6.3 Battery care
The maintenance of your handcycle is your responsibility. Poor maintenance can greatly increase the risks
of operating your cycle.
Read and understand these battery-charging instructions. Do not use any battery charger other than the
one supplied to charge your batteries; doing so may result in fire or damage to your batteries.
The batteries supplied with your handcycle are Lithium ion. This type of battery combines lightness in
weight with a very high charge capacity.
The reasonable use and above all correct charging of the battery as well as protection from deep
discharge and overheating will greatly help to prolong it’s life. A suitable charging controller, which takes
all of these requirements into account, is already incorporated into the battery box to ensure optimum,
safe operation.
There is always a certain amount of self-discharge (typically 1% per day at room temperature) the battery
should always be charged up before being used for the first time.
