kindy develop objection2

_ bike

2

Lni

«

parky M

rH
~ ]

¢
bs

11:

hours, I would expect a run time of only .38 hours, or
about 20 minutes (32 AH/83.33 amps). This assumes that
I am forcing the motor to work at its full rated capacity at
all times, and this is never the case; in reality, I typically
get 1.5 hours or more between charges, even when
spinning up dirt and pulling wheelies. A realistic measure
of run time between charges will be something you will
have to find out from actual use, as it will certainly vary.

Voltage

Each battery has a rated voltage, with 12 volts being the
most common for batteries typically needed for small
electric vehicles. Since most small electric motors run at
voltages between 24 and 48 volts, you will have to
connect two or more batteries in series to achieve the
required voltage rating for the battery pack. A series
connection means that the positive terminal of battery #1
connects to the negative terminal of battery #2, and
power is taken from the free terminal of each battery
(one positive, and one negative). In series, a battery
cannot deliver any more amp hours than the rated
capacity of a single battery, but it does double the
wattage available because it also doubles the voltage. My
two batteries shown in Figure 11-1 are rated at 12 volts,
and 32 amp hours each, so in series they deliver 32 amp
hours at 24 volts, or 768 watts (24 volts x 32 amps).

A single battery would only deliver 384 watts (12 volts x
32 amps). If wired in parallel (not recommended), the
batteries would double their amp hours to 64, but the
voltage would remain at 12 volts, so they would again
deliver 768 watts (12 volts x 64 amps). Parallel wiring
of batteries should never be done, since one battery may
try to charge the other if they are not equal, which could
result in damage, heat, or fire. To sum this up, you will
need to connect as many 12-volt batteries in series as
necessary, in order to achieve the desired voltage, but
your overall amp hour capacity will be the same as one
single battery can deliver.

price may be inviting. A car battery is made to deliver an
enormous amount of power in a very short time and then
become fully charged shortly after. As many of us know,
a car battery will be destroyed if run completely down
more than a few times in a row, which is why it will not
be a very good candidate for our purpose. Car batteries
are also very messy, require some fluid maintenance, and
do not like vibration or uneven mounting. A much better
choice for your battery needs is the non-spillable, sealed,
GEL deep cycle battery. These batteries have no
removable tops since they contain no liquid (it is ina
gelled state)—they can be mounted in every orientation
except upside down, they can withstand moderate
vibration, and they can be depleted completely many
times without damage. These batteries are commonly
rated as marine or wheelchair-use batteries, and the
smaller units may be rated for security or battery backup
use. They are more expensive than conventional car
batteries, but will outlast them many times over,
especially in our electric vehicle. Multiple batteries
should always be the same type, and approximately the
same age, especially when charging them together as a
24 or higher voltage pack.

Charger

The best way to charge your batteries is together as a
single pack, so if your battery pack voltage is 24 volts,
you will need a 24-volt charger. These are readily
available, and often you can find older ones at
secondhand stores, or from shops that repair or sell
wheelchair parts. A common 12-volt charger used fora
car battery will also work, but you will either have to
charge one battery at a time (very slow), or purchase two
chargers and run them both, one on each battery.
Whichever you choose, the charger should be fully
automatic, shutting off when the battery is at peak
capacity in order to avoid damage from overcharging.
Only the worst chargers available will not have a current
meter or automatic shutoff, and these should be avoided.

Uv Also, make sure that the charger you have is rated for the
oO B atte ry ty pe type of battery you are using, such as wet lead acid, or
1 sealed gel.

© Notall 12-volt batteries are the same, and this fact is I hope that wasn’t too much nerd jargon in sucha

{4 largely reflected in the price. Typical car batteries are not small space! It really does help to know what to expect
Q) well-suited for electric vehicle use, even though their from batteries and motors before you start searching for