Coin cell that can deliver 10ma

[Jester]

I'm looking for a coin cell that can provide at least 10ma while maintaining output voltage above 2.8V

If you look at the voltage vs. current profile for a typical coin cell (see CR2450), you will see even if they have a substantial ma/hr rating the continuous standard load specification is very low for example 200uA.

Any suggestions?

 

[jiripolivka]

Most "coin" cells are designed for a low-current load. With 10 mA load, most coin cells will discharge rapidly.
Find a "rechargeable" coin cell,or use an AA or AAA alkaline cell (two), they can live longer with 10-mA load.

 

[Jester]

No room for AA or AAA

 

[Audioguru]

Why are you using a tiny weak little battery? The datasheet of the CR2450 Lithium coin cell from Energizer rates it with a 0.39mA load. It shows it brand new with an internal resistance of about 16 ohms when its load is 9mA so its 3V drops to 2.86V. They show a 9mA load for 2 seconds 12 times per day. Its internal resistance quickly rises to 120 ohms then with a 9mA load its 3V drops to only 1.92V.

 

[Jester]

Why are you using a tiny weak little battery? The datasheet of the CR2450 Lithium coin cell from Energizer rates it with a 0.39mA load. It shows it brand new with an internal resistance of about 16 ohms when its load is 9mA so its 3V drops to 2.86V. They show a 9mA load for 2 seconds 12 times per day. Its internal resistance quickly rises to 120 ohms then with a 9mA load its 3V drops to only 1.92V.

Existing product that uses a CR2450 cell, the company now wants to squeeze additional circuitry (bluetooth module that will be used very intermittently) into the same footprint and enclosure. I can fit the components, however current requirements will be about 10ma for short bursts while the radio is active. No room for a larger battery.

 

[tggzzz]

Existing product that uses a CR2450 cell, the company now wants to squeeze additional circuitry (bluetooth module that will be used very intermittently) into the same footprint and enclosure. I can fit the components, however current requirements will be about 10ma for short bursts while the radio is active. No room for a larger battery.

Add a capacitor?

 

[Audioguru]

Yes, the capacitor supplies the short bursts of 10mA and the battery slowly charges it.
Of course the battery life will be less than it was before this Bluetooth module was added.