# batteries

Discussion in 'Electronic Basics' started by Bumble, Dec 11, 2004.

1. ### BumbleGuest

if I conect 2 1.5 volt batteries together, does this mean i have 3 volts or
a stronger 1.5 charge?

Is this the same for amps? Do the amps double as well?

2. ### Tom BiasiGuest

It depends on how you connect them together.
Tip to tail (series) add the voltage, same current.
Tip to tip,tail to tail (parallel) add the current capacity same voltage.
(unless the capacities are not really close to each other.) Don't do
parallel if the batteries are not the same voltage.
Regards,
Tom

3. ### CFoley1064Guest

Subject: batteries

Series Parallel

.------o + .------o-------o +
| | |
+| | |
1.5V --- | |
- +| +|
| 3V 1.5V ---1.5V--- 1.5V
+| - -
1.5V --- | |
- | |
| | |
'------o '------o-------o
created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de

The first connection is called a series connection. It produces 3V with two
1.5V batteries, and is perfectly OK. A connection of this type provides twice
the voltage at the same mA-H (milliamp-hour) rating as one battery. That's
twice the total power (P = V * A)

The second connection is parallel, and _may_ work out OK, depending. Usually,
hooking up battery cells in parallel is a bad idea. Most batteries have small
differences in potential due to age, usage, and the manufacturing process.
Since connecting them together means that they will have to have the same
potential, usually one of the batteries ends up partially discharging into the
other, slightly lower voltage battery, which wastes power. This occurs until
the voltages equalize. That doesn't do the lower voltage battery any good
either, especially if it's not the rechargeable type. Even the rechargeables
can be harmed by a momentary charging current greater than the recommended
maximum.

If both batteries are new, and come out of the same package, it's usually OK.
If one of them is new and one is mostly discharged, both batteries get hot, and
you end up with two mostly discharged batteries.

Theoretically, putting two batteries in parallel will give you the same voltage
as one, with twice the total mA-H (milliamps * hours to discharge). Same
voltage at twice the current = twice the power (P = V * A). But if you need
twice the power at the same voltage, it's usually a better idea to buy a bigger
battery (say, "D" instead of "C").

Good luck
Chris