What Is The Purpose Of A 12 AA Cell Large Flashlight ?

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I recently purchased this flashlight from Harbor Freight. It is an excellent flashlight for the money. It has both a "HIGH" setting, as well as a "LOW" setting. And it also has a, "SOS Strobe" setting. It is extremely bright and well made.

The only "problem" is, it takes 12, AA batteries in a removable pack. It could have been easier, (and most likely cheaper), if it had been designed to take 3 or 4 "C Cell" batteries. Or even multiple, "D Cells".

Does anyone know what is the purpose is of having so many smaller AA Cells? I would think it would last longer with the larger cells. Or is it a voltage issue of some type?

 
More cells = higher voltage.

C and D cells are outdated and obsolete.
?! Um. No. Not if you have a device that uses them. And they are still used in many, many new devices. Costco sells D and C cells in multi packs and that means they sell or they would not be on the racks.

I bought a LED lantern just this summer and the main criteria was that it take 4 D cells. These batteries will last me a couple of seasons of use with that battery pack. The lanterns with 4 AA batteries only last a few months - this I know from experience . Size matters. 😬
 
My 1980's Maglites still use c and d cells
In stock in all stores and still sell lanterns and flashlights that take 'em

You get to use longer lasting lithium AA's and rechargeables too
 
More cells = higher voltage.
Depends on how the cells are connected. I doubt they're all in series for a total of 18V. Most likely it's closer to 4.5V or 6V.

OP, how is the removable pack arranged? Is it 3 levels of 4AA cells each? Or is it 4 levels of 3 AA cells each? Would 3 D cells fit inside the flashlight?

EDIT: Found a video. It looks like 4s3p, but it could also be 3s4p, so total voltage is either 4.5V or 6V at rest, depending on how it's wired inside. Easy enough to check with a DMM. Looking at the proprietary connectors, replacing the battery pack with regular C or D cells is not going to work.

 
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The purpose is to allow the manufacturer to get away with making it as cheaply as possible.

The 12 cells are likely to be wired in parallel to have them produce ~4.5 volts to drive the LED with minimal circuitry, and give it some longer runtime and shelf life.

It's not by accident that most cheap LED flashlights are powered by triples of typical alkaline cells, to achieve that nominal figure.

Most LED flashlights utilize emitters that run nomially in the three volt range. Some larger emitters require six volts, or even twelve, which can be achieved by driver circuitry in single cell lights, or a combination of drivers and multiple cells.

It would also be surprising if that light produced the claimed 3700 lumens, considering flashlights with reputable emitters and powered by lithium cells don't always live up to their output claims. The chances that a cheap/HF alky special does aren't going to be as good.

Forty bucks can buy a good quality rechargeable flashlight that can actually produce that amount of light at max output, for brief periods, and sustain more moderate levels for hours, without diminishing brightness as cell voltage drops, if one is willing to consider of the Chinese budget brands.
 
Forty bucks can buy a good quality rechargeable flashlight that can actually produce that amount of light at max output, for brief periods, and sustain more moderate levels for hours, without diminishing brightness as cell voltage drops, if one is willing to consider of the Chinese budget brands.
The Anker LC90 is a pretty serious budget flashlight, IMO. Few different brightnesses plus flashing, $35
 
AA cells are the same length as C cells. I suspect the flashlight case was designed to take C cells or these AA packs depending on type of light output, where it's sold, etc.

In the US AA cells are available in large packages relatively cheaply compared with when I was younger. C and D cells are more expensive.

Agreed that these AA cells are probably wired partly in parallel to increase capacity (run longer), not to get a higher voltage.
 
I have to wonder if this isn’t design reuse. I don’t see a manual, but I know a lot of the cheap flashlights use a plastic holder to use 3 AAA’s. So I wonder if they have a 3x AA holder that use in this light, and other lights. One less thing to design?

I guess you can put them in parallel, I’d be concerned about cell matching, but high end equipment this is not. It just has to work until a cell leaks, right?

While it’s probably series-parallel they do make buck convertors that would take that input voltage and drive the LED with a constant current.
 
Well I wouldn't own one - but I do agree that C and D batteries are harder to find at retail, but everyone sells AA. I converted my old maglites to LED, and love them, but the D cells are expensive.

I am switching everything to flashlights with removeable 18650 Li-Ion batteries, brighter, more efficient, cheaper in the long run.
 
The purpose is to allow the manufacturer to get away with making it as cheaply as possible.

The 12 cells are likely to be wired in parallel to have them produce ~4.5 volts to drive the LED with minimal circuitry, and give it some longer runtime and shelf life.

It's not by accident that most cheap LED flashlights are powered by triples of typical alkaline cells, to achieve that nominal figure.

Most LED flashlights utilize emitters that run nomially in the three volt range. Some larger emitters require six volts, or even twelve, which can be achieved by driver circuitry in single cell lights, or a combination of drivers and multiple cells.

It would also be surprising if that light produced the claimed 3700 lumens, considering flashlights with reputable emitters and powered by lithium cells don't always live up to their output claims. The chances that a cheap/HF alky special does aren't going to be as good.

Forty bucks can buy a good quality rechargeable flashlight that can actually produce that amount of light at max output, for brief periods, and sustain more moderate levels for hours, without diminishing brightness as cell voltage drops, if one is willing to consider of the Chinese budget brands.
I've never had mine apart yet. But here is a video showing the exact same light I have. It has a twist to zoom lens. They show the battery pack at 7:20 in the video. It's not the best review, but it at least shows the 12 AA Cell pack it uses. The AA Cells are arranged in 3 rows of 4 cells each.

I think what I'll do when the batteries start to go, is replace them with a dozen AA Lithium Cells. They'll last longer, and I don't have to worry too much about them leaking. You can't trust Alkaline batteries anymore. They leak like a sieve compared to the ones produced a decade or more ago.

 
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Can you imagine how big a flashlight would be having 12 series connected C or D cells ?

I wouldn't buy such a flash light requiring 12 batteries.. The batteries probably cost more than the flashlight.
 
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I remember the old lanterns that sat on top of two huge batteries. I can't remember what they were exactly.
They apparently are just called 6v or 12v lantern batteries (a 12v is just twice the size)


Antique’s would actually pack 4x F size batteries instead of packing them together into a lantern battery (4r25)

Devices that pack in a load of double or triple A batteries instead of c or d are just plain stupid.
 
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