Tec 40 and UK Mini Q 40 on lithiums: you won't believe the results!

brightnorm

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Oct 13, 2001
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Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

After previously run-time testing the Tec 40 and the UK Mini Q 40/ 4AA with several different brands of alkaline batteries, I found that Ray-O-Vac Maximums gave the best results: A solid 3 hrs+ of good light. The test included the UK 2L, which competed nicely, giving very slightly dimmer light for 3 hrs, maybe 10-15 minutes shorter than the others.

Today I decided to test with Energizer lithiums, dated 2010 which I got from Tim Flanagan at a good price (for lithium AA's). Since I don't heavily use my lights every day, nonrechargeables are practical for me. Even lithiums would be cost effective if the burn time was good enough.

I started the first test with fresh batteries
but had to leave the house and stopped the test after almost 4 hours, at which point both lights were still doing quite well.

Here are the results of the 2nd test:

8:52 PM
Both lights very bright. Very hard to choose between the UK with its very bright hot spot, and the Tek 40 with its smoother beam.

10:33 PM
Both lights still white and bright.
UK Again, that bright Hotspot
Tek 40 the smooth beam is more like a "flood" and even though it's slightly dimmer than the UK's hotspot, I might prefer it for walking/trekking.

12 Midnight
Both lights still white and bright, both retaining the above described characteristics. A difficult choice.

12:57 AM
Both lights still quite white and bright, still retaining those characteristics; still hard to choose between them.

1:28 AM
UK still fairly white and bright
Tek 40 almost dead. I terminated it, and guess it began to crash soon after my 12:57 AM observation.

1:48AM
UK Noticeably dimmer but not yellow. Still giving off a reasonably bright, functional beam.

2:01 AM
UK Significantly dimmer but still "functional. I ended the test at this point.

Conclusions:

Both lights achieved impressive performance on lithiums. With these batteries the Tek 40 could be legitimately be considered a 4 hour light. The UK4AA easily makes it to 4 1/2 hours, and remains comfortably functional for another 15 - 30 minutes. A very conservative rating of the two lights would be:
Tek 40 3hr 45min
UK4AA 4hr 30min

These run times on lithiums are so impressive that I would now prefer either of these lights to the Surge,(which can't take lithiums) especially the UK.

I hope that other flashaholics who have appropriate measuring instruments might be interested enough to properly test these lights.

Respecfully submitted,
Brightnorm


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Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

Brightnorm!
Thank you for a great analysis. a few thoughts, first I agree with Allan that 4 lithium AA's are more costly than 2 CR123's.
What made me choose the UKQ40 over the 2L for EDC was the ability to get AA's anywhere, anytime. Also when you stock up (Surge owners know what I mean!)I have them in every drawer! In terms of brightness I think it matters most(for my applications anyway)when you are comparing one to another. I've found that the Q40 with Alkalines give me enough light for almost anything. After seeing your results, I think I'll load one of my Q40's with Lithiums for an emergency back up! The extended run time and brightness would make me reach for the Q40 over my G2 in say an earthquake. A quick question - Do the lithium AA's have the same shelf life as the CR123's? Thanks again!

Amplite
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

Amplite - according to the "battery info" section at the Energizer site they both go about ten years. From PDF files I calculated the Watt-hours per liter on the CR123's are about 492 and the L91 AA Lithiums are 536 Watt-hours per liter!
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

Thanks much for your test result info Brightnorm!

UK4AA w/ Rayovac Maximum alkaline vs UK4AA w/ Energizer AA lithium
UK4AA w/ Energizer AA lithium vs UK2L w/ CR123

Would you say that UK4AA performance with regards to price of battery, runtime, and light-output greatly favor the AA lithium or just slight advantage?

- verge -
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

Bravo Brightnorm!
My history with lithiums are less than 2 years - my question - Are lithiums less prone to leakage when in storage - do they even leak like alkalines?
Next I was told by the kind folks at Underwater Kinetics that the bulb for the Q40/4AA/2L will last 30 hours. Brightnorm I know you've had your UK lights for years. The bulbs are $6.50 +, how did yours do?

It's always something!!!
Amplite
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

Lithiums are better than alkalines at high drain. That's my experience at least. I used lithiums in a 0.5A lamp, and they didn't do better than alkalines. Actually, the run time was shorter and the increased brightness was insignificant. However, switching to lithiums in a 1.0A lamp, the difference was huge. They outperformed alkalines big time.

However, at drains more than 1.0A i prefer NiMHs. The overall run time may be a little shorter, but the light maintains "initial" brightness much longer.
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Amplite:
Brightnorm I know you've had your UK lights for years. The bulbs are $6.50 +, how did yours do?
<HR></BLOCKQUOTE>

Amplite,

It's Almost impossible for me to answer your bulb question because I have many UK's and have used, played and alternated between them in a highly disorganized manner until very recently when I became a member of CPF

So far I've had only one bulb blow in a miniQ40 with lithiums when I first turned it on, earlier in my testing. I suspect it was just about ready and that was the coup de grace!

I know nothing about battery leakage, and I've experienced only one case of it; an OLD conventional flashlight with two D cells that leaked after being in there for amost 15 years!

Sorry not to be able to give you a more satisfactory answer.

Best regards,
Brightnorm
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by recercare:
However, at drains more than 1.0A i prefer NiMHs. The overall run time may be a little shorter, but the light maintains "initial" brightness much longer.<HR></BLOCKQUOTE>

recercare,

I'm interested to know which light you'e referring to and how long you got it to run with good brightness with NiMHs. Did you do comparative run time tests? That would be a really useful post.

I've always assumed runtime was short with rechargeables, but it's certainly possible that I'm wrong, or uninformed about specific applications such as the one you mentioned

Best regards,
Brightnorm
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

Norm, modern Nimh cells aren't too wimpy these days-example: AAs rated to deliver 1800mAh
shocked.gif
and you can recharge 'em at any time you like.
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Amplite:
Bravo Brightnorm!
My history with lithiums are less than 2 years - my question - Are lithiums less prone to leakage when in storage - do they even leak like alkalines?
<HR></BLOCKQUOTE>


According to my understanding, Lithium don't leak. there is nothing liquid in the batt itself to leak. so u can safely put lithium in anything and store them for yrs in hot or cold places. another thing, try putting Alkaline batt in a Flashlight and put it in hot places (direct sun), U wouldn't even bother cleaning up the mess.
Linfeng
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

Amplite,

I see no reason to doubt LightBright's figures on lithium shelf life. When it comes to alkalines however, I've always questioned those 6-7 year post-dates. Any flashahoilic know for sure?

2d_edge,

It's really hard for me to answer your question because it's a personal decision based on application, need and preference. One reason I test so many lights is to try to find the best ones for my specific purposes.

Price is not a major consideration for me; not because I'm affluent, but because I don't use my lights heavily every day, in which case I'd still be tempted to use alkalines or lithiums because of their significant run time advantage over rechargeables. As you can probably tell, run time is a critical issue for me. With present technology there's no such thing as a very small, very bright light with a long run time. My Asp Taclite (now the Asp Triad), is remarkably bright, and I carry it just for that quality, not for its runtime.
I consider the 4AA or the 2L as back ups to the Asp. Actually, i just realized that my thinking is inaccurate since the UK's are used as general "everything" lights, and the Asp is used for specific purposes. If it was my primary light I'd exhaust the batteries within the first hour of use.

Along with others in our group I'm an enthusiastic advocate of redundancy. I even back up my backups. (Asp, UK 4AA/2L,Inova X5, Arc AAA LE HA, Photon and Inova microlites! I've found this "philosophy of redundancy" very useful in many areas of life. Quick, slightly dumb example: A couple of years ago my girlfriend found some really great undershorts for me. I bought about 30 of them, which she and others thought was ridiculous. Two years later the Company is now out of existence, but I still have all those shorts! And if they still were around they would probably have "improved" the product in some negative way, which I see happen very often. In this case the redundancy was of the same product. With flashlights we more commonly back up with a different product.

I'll get off my soapbox now and back on topic....

4AA/2L with Ray-O-Vac Maximums: figure a 3 hour practical run time, perhaps a few minutes more for the 4AA over the 2L, with the 4AA maintaing a slight brightness advantage over the 2L.

To repeat my test figures, the practical UK runtime with lithiums is 4 1/2 hours. For the Tek forty is about 3 3/4-4 hours.
That's almost a 50% increase in runtime for the 4AA. I find that remarkable and immediately convincing. The MiniQ40 with lithiums will now go on my belt for EDC.

Best regards,
Brightnorm.


<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by 2d_edge:

Would you say that UK4AA performance with regards to price of battery, runtime, and light-output greatly favor the AA lithium or just slight advantage?
- verge -
<HR></BLOCKQUOTE>
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

Brightnorm,

For low/midium current load, alkaline outperform rechargeables in runtime. However, if you use high load like 1.0A, I believe NiMh will beat alkaline.

Simple test - try put 4AA in Surge and see how long its brightness last. Test it again on 4 NiMh and you will see.

Alan
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

It's been a while since i did the comparison between alkalines, lithiums and NiMHs. I don't remember the exact results. I have some time off on Sunday, and will do a new test then.

When I measure run time between alkalines and lithiums I stop when the light is no longer useful. In other words, when the battery reaches 0.8V. (this is a valid limit on most occations)

When comparing with NiMH it's more complicated because the NiMH maintains voltage until empty (or at least almost empty).

-I let the Lithiums and Alkalines run until 0.8V/Cell and at the same time measuring lux every hour. That means I'll get the total useful run time and some clue about the decreasing brightness/hour
-I'll let NiMH run until almost dead. Voltage will stay at 1.8-1.2V regardless of capacity, so measuring voltage is not neccessary...but I'll measure lux every hour though.

Test objects: DB8AA (0.35A) and Sigma Mirage (1.0A).
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Alan:
For low/midium current load, alkaline outperform rechargeables in runtime. However, if you use high load like 1.0A, I believe NiMh will beat alkaline.
<HR></BLOCKQUOTE>

Alan,

I'm sure you're right. I've never used rechargeables or a recharger,and am not at all knowledgeable about them. My usage pattern is most likely to be fairly long periods of non-use interspersed with random periods of moderate to heavy steady use. Basically, I want a light that is ready at any or all times to give me a long run in any weather. I think lithiums best fit this profile. I haven't kept up to date on rates of discharge over measured time periods (ie: x% loss per day or week, etc) in the various types of rechargeables.

It may be that I'm missing out on something good here, and I find the ability of NiMhs to maintain brightness until the bitter end very appealing. I'm looking forward to the results of recercare's tests.

Best regards,
Brightnorm

.
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by recercare:

-I let the Lithiums and Alkalines run until 0.8V/Cell and at the same time measuring lux every hour...., ...but I'll measure lux every hour though.
Test objects:
<HR></BLOCKQUOTE>

Recercare,

I must admit my ignorance: what does LUX mean? Please explain in layman's terms.

Thanks,
Brightnorm
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

brightnorm:

Lithiums sound like the best choice according to your needs. The NiMHs selfdischarge about 30%/month compared to lithium's 2-5%/month. NiMHs are lousy in cold weather as well, and even though it's appealing to keep up brightness for long time it's also risky because you don't get an indication about battery capacity. The light is bright, then suddenly drops dead before you're able to get back getting those extra batteries you forgot to bring with you.
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by recercare:
brightnorm:

...Lithiums sound like the best choice according to your needs...
<HR></BLOCKQUOTE>

Recercare,

That's useful info. Thanks

Best regards,
Brightnorm
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

Amplite and Chris M,

Belated thanks for support in previous thread.

Best regards,
Brightnorm
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

It's a measure for illumination, or the brightness that falls upon a surface. It's the same as footcandle except that the unit is meters not feet. One lux is one lumen per square meter.
 
Re: Tec 40 and UK Mini Q 40 on lithiums: you won\'t believe the results!

OK, thanks

BN
 
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