What is the range of currents that I can safely draw out of a 9V battery without damaging it?

I am planning to design an experiment and I don't want to draw too much of current out of a battery and damage it.

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    \$\begingroup\$ What did you find? Max 500mA depending on type? A google search gives : forum.arduino.cc/index.php?topic=132106.0 \$\endgroup\$ – Solar Mike Dec 24 '18 at 6:34
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    \$\begingroup\$ I tried googling but I did not arrive at a conclusive answer. Thank you for your link. \$\endgroup\$ – Ampersand Dec 24 '18 at 6:44
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    \$\begingroup\$ To use them is to damage them,. even a 1mA current will eventually lead to it going flat. \$\endgroup\$ – Jasen Dec 24 '18 at 8:00
  • \$\begingroup\$ Design your experiment to use less than \$40\:\text{mA}\$ and work well over a voltage range of \$7.5\:\text{V}\$ to \$9\:\text{V}\$. You'll be fine, then. \$\endgroup\$ – jonk Dec 24 '18 at 10:13

This depends widely on the battery chemistry, size and manufacturer.

It is directly dependent to the serial resistance of the battery and the heat generated during discharge.

You should find the specific battery datasheet and look for the discharge current.

Some datasheet will give you a value in Amp, other will give you a value in C, like "2.5C" which refers to the battery Amp Capacity in A or mA. If the battery is 2500mA, 2C would mean 5Amp, 0.5C would mean 1.25Amp.

For standard 9V batteries, this information is not always available, but these batteries are not designed to deliver high load.

This datasheet shows a discharge rate of 150mA continuous, at this rate the battery would be done in about 8 hours.

Given this is a high end battery, I would not get over 100mA discharge rate for a standard 9V battery.


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