-
Lithium coin cell battery to power LED?
i bought a 2AA battery holder and am using that to power my LED that i'm going to use in my crystal chamber.
however, i also have a 3V CR2032 lithium coin style battery.
i held my 5mm 3.7V 20mA 2600mcd blue LED to the coin itself and it lit as brightly as ever.
this is probably a dumb question, but why are these types of batteries not used to power LED setups inside lightsabers rather than 2AA batteries in a battery holder which would be equivalent to 3V anyways.
just at about 10 times the size consumption within the hilt.
this is basically what i'm talkin' about:
http://www.amazon.com/gp/product/B00...V012QYMRMNH8SS
and here's a pic of mine, with my 5mm LED.
Last edited by ghost_a*; 01-09-2011 at 02:03 PM.
-
-
The answer is a simple one. Capacitance. As an example, two AA NiMH Batteries average around 2000 mA which if you were to run a high power LED at 500 mA, your LED would stay lit for about 4 hours. The coin cell batteries, while small, have nowhere near that kind of capacitance and in turn would only give you a moment or two before the battery is drained. LED's are current sensitive devices, not voltage sensitive. You can run an LED over the recommended voltage as long as you are limiting the current into it. Make sense?
-
Council Member
Jedi Padawan
Many reasons. First off, most these batteries are primary type. Meaning they are not rechargeable and will need to be replaced when they die. You will be replacing them often in a saber if you use them. Second, and most importantly, they just don't have the discharge current. A quick Google search yilds a Sanyo spec sheet. These cells are rated for a maximum continuous discharge rate of 4 mA with a pulsed discharge rate of 20mA. Since your LED wants 20mA to run properly, your CR2032 will nto last very long and you might even ruin your LED. It's just easier to run the crystal chamber LED of the main power supply and resist as necessary.
-
totally answered my question
thanks guys
i'll stick with the 2AA battery holder.
Posting Permissions
- You may not post new threads
- You may not post replies
- You may not post attachments
- You may not edit your posts
-
Forum Rules
Bookmarks