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I have been working in a simple LED project which will draw 200mA from the supply. I need the project to be portable, so decided to go with CR3032 Battery product link. It is rated 500mah, i should be able to run my project for 2 hours at least and that's enough for me.

While checking the product page i have noted Discharge Rate - 200µA . I don't understand what exactly this convey.
1) So am wondering that if i could even draw draw 200mA from this battery and power my project?
2) What exactly does the Discharge rate info convey?

P.S : I am a newbie, still working my way in Electronics tinkering. Kindly advice :)

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So am wondering that if i could even draw draw 200mA from this battery and power my project?

No. Coin cells are intended for low current applications such as keeping a real time clock powered. They are not intended to to deliver any significant power. Look at this graph in the datasheet.

CR3032 capacity vs discharge current

Capacity starts rolling off over ~1.5mA. You will have no usable capacity at 200mA, if the battery can even deliver 200mA.

What exactly does the Discharge rate info convey?

Continuous standard load is basically the maximum constant current load where you can expect to get the rated capacity.

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    \$\begingroup\$ The other graph shows that at 2.4 mA load, the cell voltage will drop to 2.4V (from 3 V nominal), which means that the internal resistance is about 600 mV /2.4 mA = 250 Ohms. There is no way whatsoever this cell can deliver 200 mA, and even if you short it, the current will be about 12 mA. This is all in the datasheet. \$\endgroup\$ May 13 '17 at 4:14
  • \$\begingroup\$ I exactly had this question in mind and very glad to find answer for this :) \$\endgroup\$ Aug 16 '17 at 4:44
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Those types of batteries are designed for low currents over long periods. If you attempt to take a higher current the terminal voltage will drop, maybe to the point that your circuit will not work.

The CR3032 seems to be fairly rare but I did find information about the more common CR2032. This has about half the capacity of the one you chose.

This paper (Coin cells and peak current draw) implies that the internal resistance is probably in the 5-10 ohm range. A 200mA draw would drop about 1-2V.

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