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INCREASING BATTERY RATINGS 189

9-volt N A A A A A C D

Figure 18- 7 Comparison of
consumer battery sizes, from N to
D cell, plus 9- volt.
the internal area of an AA battery, it stands to reason that the capacity of a C battery is about
twice that of the AA cell. (In actual practice, size versus capacity is more complicated than this,
but it’ll do for a basic comparison.)

ON THE
There’s more about batteries, battery sizes, and selection on the RBB Online Support site (see
Appendix A for more details).
W E B
Increasing Battery Ratings

Through the magic of electricity, you can get higher voltages and current by connecting two
or more cells together. Increasing volts or current depends on how you wire the batteries
together:
+ To increase voltage, connect the batteries in series. The resulting voltage is the
sum of the voltage outputs of all the cells combined. This is the most common
way to connect batteries.

-
+
To increase current, connect the batteries in parallel. The current is the sum of
the current capacities of all the cells combined.

-

Take note: When you connect cells together, not all cells may be discharged or recharged
at the same rate. This is particularly true if you combine two half- used batteries with two new
ones. The new ones will do the lion’s share of the work and won’t last as long. Therefore, you
should always replace or recharge all the cells at once. Similarly, if one or more of the cells in
a battery pack are permanently damaged and can’t deliver or take on a charge like the others,
you should replace it.

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