Which Battery for a D10?

[jag-engr]

I currently have an EX10. In the past, I have shied away from AA lights because I felt they weren't bright enough, and, in the case of the Fenix L1D, just a little too long. Due to the shorter length of the D10, the higher AA output of the D10, my recently obtaining Duracell-Eneloop batteries, and the announcement of the upcoming D20, I am considering trading the EX10 for a D10 (maybe with a GDP emitter) and converting all my flashlights to AA or AAA batteries.

I found this is nascar's NiteCore D10 - EX10 Review. The third chart down shows the output and runtime for E2 L91 (Energizer's 1.5V Lithium AA ?), an Eneloop, and an alkaline (in order of decreasing performance).

Primarily, I would like to know how Eneloops perform in the D10 in regards to heat. I remember reading that it gets rather hot if driven on high with alkalines. The Eneloops, I believe, have a lower output - 1.2V. Do they get even hotter, or does their better chemistry compensate for their slightly lower voltage?

I'm sure the lithiums don't heat up nearly as bad, but they are also more expensive and would be used more as back-up batteries.

No doubt, 3.7V protected rechargeables would be ideal, but I don't want to mess with the finnicky battery chemistry.

 

[superflytnt]

I currently have an EX10. In the past, I have shied away from AA lights because I felt they weren't bright enough, and, in the case of the Fenix L1D, just a little too long. Due to the shorter length of the D10, the higher AA output of the D10, my recently obtaining Duracell-Eneloop batteries, and the announcement of the upcoming D20, I am considering trading the EX10 for a D10 (maybe with a GDP emitter) and converting all my flashlights to AA or AAA batteries.

I found this is nascar's NiteCore D10 - EX10 Review. The third chart down shows the output and runtime for E2 L91 (Energizer's 1.5V Lithium AA ?), an Eneloop, and an alkaline (in order of decreasing performance).

Primarily, I would like to know how Eneloops perform in the D10 in regards to heat. I remember reading that it gets rather hot if driven on high with alkalines. The Eneloops, I believe, have a lower output - 1.2V. Do they get even hotter, or does their better chemistry compensate for their slightly lower voltage?

I'm sure the lithiums don't heat up nearly as bad, but they are also more expensive and would be used more as back-up batteries.

No doubt, 3.7V protected rechargeables would be ideal, but I don't want to mess with the finnicky battery chemistry.

I run my D10 on NiMH's quite often, as well as lithium primaries, and it gets a bit warm but nothing that I'd consider hot at all. I can tell that it's above ambient 70'F but the D10 is actually not driven too hard so heat isn't much of a problem............................

 

[Gator762]

Do some searches, someone provided some runtime graphs with the D10. The output was a bit higher with a 14500 cell, but run time slightly less and not ruler flat regulation.

The safer chemistry is also a bonus with NiMH.

 

[wacbzz]

Didn't those same runtime graphs referenced above show that while the D10 with a 14500 is initially brighter, it quite soon goes down to the same regulated output with as that with a primary AA? I just ordered a D10 myself and was wondering this very same question...Perhaps though I was reading the charts wrong.:thinking:

 

[rocled]

I run mine on a 14500 due to the higher output on max. I have not had any problems with this battery, but follow all the rules of Li-Ion. And on high, after 10 minutes the light reaches 106 F with an ambeint of 73. If you run your light on high all the time, yeah it will get warm. But for medium output, the light never gets too warm.

 

[wacbzz]

I run mine on a 14500 due to the higher output on max. I have not had any problems with this battery, but follow all the rules of Li-Ion. And on high, after 10 minutes the light reaches 106 F with an ambeint of 73. If you run your light on high all the time, yeah it will get warm. But for medium output, the light never gets too warm.

Does this output with the 14500 stay "high" for very long? I'm just wondering if the output with a primary AA stays level for a longer time than the 14500...

 

[rocled]

www.candlepowerforums.com/vb/showthread.php?t=201647
Try this, the fourth graph. There is a slight drop off with the 14500, but throughout the charge of the battery the light stays at the same light level, which is higher output than a primary.

 

[wacbzz]

Awesome. Thanks.

 

[rocled]

Also with the 14500 being 3.7 volts, the D10 has to "buck" the current, so the light will maintain a stronger output without the light dropping off, unlike alakline or eneloops where the voltage is weaker and drops off, dimming the light as the batttery dies.

 

[wacbzz]

Also with the 14500 being 3.7 volts, the D10 has to "buck" the current, so the light will maintain a stronger output without the light dropping off, unlike alkaline or eneloops where the voltage is weaker and drops off, dimming the light as the battery dies.

But looking at that fourth graph leads me to believe just the opposite of what you write concerning a 14500 vs the Eneloop. From the way I'm reading it, the 14500 drops continually during the first 25 or so minutes (that will surely be noticeable to the eyes) and then keeps a constant level for about the next hour or so. I see exactly the opposite for the Eneloop; a slight drop then rise and then an almost constant output for about an hour. It seems that the Eneloop doesn't dim noticeably as the battery dies whereas the 14500 dims considerably at first as the battery is using/losing power and then levels out to a constant, albeit slightly brighter level than the Eneloop.

Am I reading this graph wrong?:shrug:

 

[Marduke]

I think the D10 and EX10 are boost only, so with a fresh cell you just get a direct drive light. Once the cell voltage drops below about 3.6v, the light goes into boost mode and it's fully regulated. On a NiMH cell, it's in boost mode the entire time.