Page 211 - Robot Builder's Bonanza

180 ALL ABOUT BATTERIES

Figure 18- 1 Desktop robot (this one uses
tracks) hides its battery supply under an
expansion panel. There’s room for additional
batteries (as needed) or a larger battery
holder.

• Batteries are by far the most common and among the least expensive methods of power-
ing any mobile device. Batteries can be grouped into two broad categories: nonrecharge-
able and rechargeable. Both have their place in robotics, and cost and convenience are the
primary factors dictating which to use. These issues are discussed throughout the chapter.
Figure 18- 1 shows a robot and its power source— ordinary household batteries in a conve-
nient holder.

Batteries for Your Robots

While there are hundreds of battery compositions, only a small few are ideal for amateur
robots.

CARBON- ZINC

Carbon- zinc batteries are also known as garden- variety “flashlight” cells: because that’s the
best application for them— operating a flashlight. They’re an old technology and not up to the
task of running a robot. Let’s move on.

ALKALINE
Alkaline batteries (not to be confused with Hall- of- Famer Al Kaline of the Detroit Tigers) offer
several times the operating capacity of carbon- zinc and are the most popular nonrechargeable
battery used today. Robotics applications tend to discharge even alkaline batteries rather
quickly, so a bot that gets played with a lot will run through its fair share of cells. Good per-
formance, but at a price.

Alkalines are also available in a super- duper form; these go by a variety of self- descriptive
G names, like Monster and Ultra. High- capacity alkalines are made for loads demanding higher
power. They’re pretty expensive, though, making them best suited as emergency backup power,
in case your regular robo batteries get unexpectedly worn out.

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