Batteries for LF EO-E2R lamp assembly?

This bulb draws 0.85Amps on 2xRCR123 cells. You should be fine, but at this current draw expect battery capacity to be around 500-550 mAh.
 
You can use the RCR's since the current draw is fairly low, but it'll be a little brighter on the IMR's. And if you have an E2e with a really tight body, the RCR's might not fit.
 
You can use the RCR's since the current draw is fairly low, but it'll be a little brighter on the IMR's. And if you have an E2e with a really tight body, the RCR's might not fit.
Why will it be brighter?(sorry im still learning when it comes to battery set ups.) Will the run time be better with them also?
 
Runtime will be about the same, perhaps a slight edge to the RCR at that low discharge rate. At 1 amp and above the IMR16340 cell wins. Below 1 amp discharge and the RCR123 is a little better.

The lamp will be brighter because the lithium manganese IMR cells have lower internal resistance than the lithium cobalt black label RCR's.
 
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Runtime will be about the same, perhaps a slight edge to the RCR at that low discharge rate. At 1 amp and above the IMR16340 cell wins. Below 1 amp discharge and the RCR123 is a little better.

The lamp will be brighter because the lithium manganese IMR cells have lower internal resistance than the lithium cobalt black label RCR's.

To summarize the 2nd paragraph: At the same discharge rates, IMR cells have a slightly higher voltage than the ICR ("RCR") cells. Less internal resistance = More voltage = more power = more brightness :)
 
Please forgive my correcting your statement, but the sake of accuracy.

Less Internal Resistance = Less Voltage Drop = Higher Vs = More Brightness.

That's fine. And sure, there are many equalities that you can add into that statement.... but I'm not exactly sure what makes my statement less accurate. I guess you could say that you're 'adding more relevant information' rather than mine being wrong.

Where I got my statement from was the [simplified] equation V = E - Ir. If r (internal resistance) decreases, then V (voltage) increases :)
 
That's fine. And sure, there are many equalities that you can add into that statement.... but I'm not exactly sure what makes my statement less accurate. I guess you could say that you're 'adding more relevant information' rather than mine being wrong.

Where I got my statement from was the [simplified] equation V = E - Ir. If r (internal resistance) decreases, then V (voltage) increases :)

:D

No arguing the equation, just that when you look at the closed circuit of a battery light system you have to take more than just the resistance of the cell into account. Obviously we know there is no perfect power source - they all have an internal resistance of some sort - and this resistance is what causes cells to heat up at higher loads - the cell drops votage just like the bulb.

An accurate way for view the closed circuit of the system for a light would be:
Battery -> R battery -> R case and wires -> R switch -> R bulb -> Battery

This is the best picture I could find:
rsint.gif



So for any level of current voltage is dropped across every resistive component in the closed loop: the battery, the case, the wires, the switch, and the bulb. We design a system such that the bulb ideally drops all of the voltage, but since that is not real the system is impacted by small voltage drops along the way.

For the RCR123 battery versus the IMR16340 battery both technically have the same nominal Vs of 3.7 volts; however, the IMR16340 has a lower internal resistance. So in the scope of the closed loop system of the flashlight when you add up all of the resistances you will see that the IMR cell will "drop" less voltage than the RCR123.

The Vs - Vinternal = Vin.

So my statement that the battery drops less voltage is more accurate than your statement that the battery voltage increases because it doesn't increase. They are both providing nominal 3.7 volts.
 
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