Breaking News
Comments
Newest First | Oldest First | Threaded View
Page 1 / 2   >   >>
ThermalHunter
User Rank
Rookie
re: The impact of high pulse drain on CR2032 coin-cell battery capacity
ThermalHunter   1/5/2012 6:36:44 PM
NO RATINGS
In the early 90's I worked for a company where long life (5 yrs at room temp, 2 years at -20C) was manditory from CR2430 coin cells in a high pulse\low average current regime. We developed a custom test which emulated the pused operation and so could predict battery lifetime. There were large (2:1 - 3:1) variations between manufacturers for the "same" battery. The discharge curves were like fingerprints; it was clear which "brands" were mearly OEM versions from other manufacturers.

studleylee
User Rank
Manager
re: The impact of high pulse drain on CR2032 coin-cell battery capacity
studleylee   1/5/2012 5:14:14 PM
NO RATINGS
Good reference info guys. thanks to authors and commentators. -Lee

mema0
User Rank
Rookie
re: The impact of high pulse drain on CR2032 coin-cell battery capacity
mema0   1/5/2012 4:22:59 PM
NO RATINGS
The TI link is: http://www.ti.com/lit/wp/swra349/swra349.pdf Using a capacitor in parallel is useful. However, remember that you have different states in Ble. The duty cycle is not the same in all states, which means that you have to make sure that you capacitor is properly loaded in cases several TX/RX activities are done at short intervals. So a smaller TX/RX current is also an advantage there.

bcarso
User Rank
Rookie
re: The impact of high pulse drain on CR2032 coin-cell battery capacity
bcarso   1/5/2012 1:57:35 AM
NO RATINGS
Coin Cells and Peak Current Draw Texas Instruments Mathias Jensen White Paper September 2010 This is worth checking out. I can't post the link directly but it was also an EETimes featured article --- a Google search ought to be productive. Note that it discusses both capacitor optimization and differences among battery manufacturers. Brad Wood

zeeglen
User Rank
Blogger
re: The impact of high pulse drain on CR2032 coin-cell battery capacity
zeeglen   1/4/2012 11:36:55 PM
NO RATINGS
I think the intent of the article is to show the response of the cell alone, not how to compensate. Yes, a capacitor would certainly help; that would be good information in a follow-on article.

Mac_H
User Rank
Rookie
re: The impact of high pulse drain on CR2032 coin-cell battery capacity
Mac_H   1/4/2012 11:27:36 PM
NO RATINGS
These are results from one specific brand of batteries - it is worth remembering that it can change dramatically for different brands. We ran some tests and found that more complex battery packs with internal temperature sensors were even *faking* safety-critical data - the manufacturer had saved money by simply removing the temperature sensor and faking the results! The graphs (and photos of the internal teardown) are here: http://bit.ly/tCTPVC

gah4
User Rank
Manager
re: The impact of high pulse drain on CR2032 coin-cell battery capacity
gah4   1/4/2012 11:09:37 PM
NO RATINGS
A reasonable-sized capacitor would help for very short pulses, but as the pulse length increases (at constant average current) the needed capacitor will eventually be too big. Well, one has to do the experiment to find where that point is.

bcarso
User Rank
Rookie
re: The impact of high pulse drain on CR2032 coin-cell battery capacity
bcarso   1/4/2012 6:00:45 PM
NO RATINGS
You're not missing anything! It's astonishing that the authors don't even mention capacitors in parallel to improve performance, which is a time-honored strategy. I speak from personal experience, having determined optimal strategies for coil cell use in certain wristwatches, ones that use electromechanical displays. Brad Wood

jeremybirch
User Rank
CEO
re: The impact of high pulse drain on CR2032 coin-cell battery capacity
jeremybirch   1/4/2012 5:00:55 PM
NO RATINGS
I am probably missing something here, but if the issue here is pulse current drain on the battery due to intermittent high current use, then surely most of the issues go away if there is a capacitor in parallel with the battery in some way? This way the pulse current comes from the capacitor (which has a much lower IR) and the battery has a long time to top the capacitor back up before the next pulse.

psi123
User Rank
Rookie
re: The impact of high pulse drain on CR2032 coin-cell battery capacity
psi123   1/4/2012 4:23:20 PM
NO RATINGS
They do not have to be tested all the time.

Page 1 / 2   >   >>


Most Recent Comments
sprite0022
 
Sheepdoll
 
DMcCunney
 
alex_m1
 
Wnderer
 
betajet
 
betajet
 
DMcCunney
 
betajet
EE Life
Frankenstein's Fix, Teardowns, Sideshows, Design Contests, Reader Content & More
Max Maxfield

Some Days You're the Pigeon, Others You're the Statue
Max Maxfield
5 comments
I was watching the travel channel on television the other evening. It was some program about Madrid. The thing I really noticed was the plethora of statues all over the place.

EDN Staff

11 Summer Vacation Spots for Engineers
EDN Staff
20 comments
This collection of places from technology history, museums, and modern marvels is a roadmap for an engineering adventure that will take you around the world. Here are just a few spots ...

Glen Chenier

Engineers Solve Analog/Digital Problem, Invent Creative Expletives
Glen Chenier
15 comments
- An analog engineer and a digital engineer join forces, use their respective skills, and pull a few bunnies out of a hat to troubleshoot a system with which they are completely ...

Larry Desjardin

Engineers Should Study Finance: 5 Reasons Why
Larry Desjardin
46 comments
I'm a big proponent of engineers learning financial basics. Why? Because engineers are making decisions all the time, in multiple ways. Having a good financial understanding guides these ...

Flash Poll
Top Comments of the Week
Like Us on Facebook
EE Times on Twitter
EE Times Twitter Feed

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)