Question on battery basics

[Zephon]

I don’t really know where to post this but flashlights/torches don’t run on magic so might as well post my battery questions here.

1.  What is the difference between 1pc 9V battery (the brick) versus say, 6pcs 1.5V  AA, C or D size batteries? 

2.  What is the difference between 1pc of 1.5V AA versus AAA (then versus C or D sizes)?

I’m not sure what the technical term on the differences are — amps?endurance?something?

My line of thinking looks to answer the question ‘Is it better to get a flashlight/torch running 1pc AA battery than 1pc AAA batteries?’ Or is it better running 2pcs AA (or 2pc AAA) than 1pc AA?

Thanks!

[nate j]

OK, I’ll take a stab at this.  Feel free to ask follow-up questions.


Before we can get to the differences between batteries, we need to define some terms:

Volt (V):  A unit of electric potential.  If we consider the analogy of electricity being kind of like water (an imperfect but useful analogy), this would be the water pressure.

Amp (A):  A unit of electric current.  Using the water analogy, this would be the flow rate

Milliamp (mA):  0.001 A

(Nominal) Capacity:  The amount of electric charge stored in a new/fully charged battery.  For handheld-size batteries, this is often given in units of milliamp-hours (mAh).  Using the water analogy, this would be like total volume of water.

Maximum Allowable Draw:  The maximum current that a battery is rated to supply continuously.

Series:  Batteries connected in series have the positive terminal of one battery connected to the negative terminal of the next battery and so on.  The maximum draw of series-connected batteries will be the same as a single battery, but the potential will be the sum of the individual potentials (e.g. two 1.5 V batteries connected in series will supply 3V)

Parallel:  Batteries connected in parallel have all positive terminals tied together and all negative terminals tied together.  The potential of parallel connected batteries will be the same as a single battery, but the maximum draw will be the sum of the individual maximum draws.


So, looking at common 1.5 V batteries, say AAA, AA, C, D, the capacity and the maximum allowable draw both increase as the size of the batteries increases.

A number of other factors can impact battery performance, including chemistry, age, operating temperature, draw, etc.

In terms of selecting flashlights, I would urge thinking more about the how you will use the flashlight, how you will carry it, what it’s specifications are (these used to be frequently misleading or inflated, and sometimes still are, though this has been somewhat better since the introduction ANSI FL1 standard), and what your sweet spot is that balances size and weight vs. performance (brightness, runtime, throw) and other options and features.

[enki_ck]

Excellently explained.

Also to add, a 9v brick wouldn't be 6x AAA, but 6x AAAA batteries. Some were even made that way.

And you can use adapters to convert AAA to AA for example and run AA flashlights on AAA batteries, but with less capacity.

[DavisNikolov]

In my quite modest experience with flashlights I can tell you this - rechargeable AA last much, much longer on a single charge than any non-rechargeable AA out there. So the initial cost of buying them will be worth it after ten or so charges and they usually last several hundred. 
Also, only had one flashlight (which I gave as present) with 18650 battery but I’m pretty impressed with the power and endurance of that type of battery. And it was a cheap-ish off brand flashlight.

[Tasky]

My line of thinking looks to answer the question ‘Is it better to get a flashlight/torch running 1pc AA battery than 1pc AAA batteries?’ Or is it better running 2pcs AA (or 2pc AAA) than 1pc AA?

More batteries of larger size generally means brighter and/or longer lasting... but also bigger in the hand.

The answer to your question depends greatly on what you want in terms of torch size and performance.
For example, the Fenix E12 is a single AA torch with a decent light output, that fits the piocket and hand very comfortably if you want to carry one every day alongside your SAK or MT. Being only a single AA means you can carry a spare battery without too much pocket bulk. The Fenix E01 is a single AAA keychain-sized torch and could almost fit in your wallet, including the spare cell... but their LD05 takes 2 AAA cells and is a little bit bigger than a pen.
By comparison, a 2 D-Cell torch might be a little bit brighter, but it's SOOOOOOO much bigger and heavier - You'll likely need a belt hanger to carry it and a separate belt pouch for spare batteries!

I have a couple of AA ones, and just to confuse you there is also the 14500 cell, which is AA sized but rechargable and of much higher voltage - 14500 torches can usually run on AA, so you can grab some from a camping shop or petrol station in an emergency... but most AA torches can NOT cope with a 14500 cell.
A popular example is the Lumintop Tool V2.0.

For daily use, I generally carry a torch that runs on 16340 cells, but for higher performance I also have a few that use 18650 cells. Most of these odd batteries are best charged in a dedicated charger, with the added advantage that these'll also charge standard AA/AAA/C/D cell batteries too.

[Aloha]

Great question and answers.  I have long got away from using non rechargeable cells.  I use Eneloops tho I do have a few other brands.  I like AAA size lights tho I do carry AA lights that can use 14500s. 

I have not bought AA or AAA cells in years so the cost of my Eneloops was well worth it.   

[fuyume]

rechargeable AA last much, much longer on a single charge than any non-rechargeable AA out there.

This really needs to be qualified. I have yet to see any rechargeable AA cell that can outlast an Energizer L91 lithium primary, whose capacity is on the order of 3000-3500 mah.

https://data.energizer.com/pdfs/l91.pdf

This compares with the Energizer NiMH AA at 2300 mAh and the Sanyo eneloop AA at 2000 mAh.

https://data.energizer.com/pdfs/nh15-2300.pdf

https://eneloop101.com/wp-content/uploads/2017/02/HR-3UTGB.pdf

Useful battery life is always dependent on current demand, and certain types of rechargeables will give greater useful runtime at higher current demands than the typical alkaline cells, but under low current demand and occasional use scenarios, the alkaline will likely be a clear winner, because rechargeables usually have a lower nominal voltage (typically 1.2 V for NiCad and NiMH) and are subject to self-discharge.

[fuyume]

sorry about the accidental double post

[DavisNikolov]

This really needs to be qualified. I have yet to see any rechargeable AA cell that can outlast an Energizer L91 lithium primary, whose capacity is on the order of 3000-3500 mah.

https://data.energizer.com/pdfs/l91.pdf

Yep, that Energizer will beat my 2100 mah rechargeable Varta, no doubt. I was not aware of that model.
I was referring to my own experience with AAs from the nearest supermarket, best alkaline that are widely spread around here being Duracell and Toshiba probably. Which are easily outlasted by the above mentioned Varta by a great margin.

[Zephon]

Great discussion everyone! Replies are very much appreciated.

[dks]

I generally use rechargeables and eneloops work well. Most current rechargeables work fine and I even had good luck a few years ago with some cheap 4000mAh or so eBay batteries.

Regarding alkaline AA capacity I did some tests a few years ago and not all are the same.

I choose Alkalines when there is a risk that the battery will be depleted totally, like if a child is using a cheap torch and they leave it on until the battery goes totally flat. This will seriously affect rechargeables, killing an expensive battery.


Some smart pieces of equipment will stop running before the battery is depleted, protecting it.

Rechargeables also work better in high current situations, like in camera flashes.There are some speSmurfpillsed rechargeables for low drain situations too, like in cheap, low lumen solar lights.

I also have 9V rechargeables for certain pieces of equipment, that work well.

Primary lithiums have great shelf life but tend to be expensive.

Most of my torches, the brighter ones use Li-Ions.

end of rumbling ....

[Tasky]

I choose Alkalines when there is a risk that the battery will be depleted totally, like if a child is using a cheap torch and they leave it on until the battery goes totally flat. This will seriously affect rechargeables, killing an expensive battery.

I understand alkalines are widely disparaged and shunned among the torch fanboy community, being known as alkaleaks for obvious reasons.
I actually only have a few torches for which I use alkalines, one being an original E12 because it doesn't take any other, and two being Maglites that I've had since the early 90s and that come with memories. I usually use the el-cheapo multipacks from IKEA, again just because.

[Zephon]

Hi everyone, I have another battery basics question here.

Given: Lumintop Frog on a 10440 battery.

I got this tube that supposedly allows the Frog to use regular AAA batteries. Here’s the thing- the tube was designed for 2x AAA

BUT when assembling it to the Frog, the said AA tube attaches to the head then the 10440’s body attaches to the tail end of the tube. To make the batteries come in contact, a total of 3x AAA are physically needed.

My question is that ‘will it work?’ Does can a light powered by a single 10440 be replaced with 3pcs AAA?

I tried it but it didn’t light up so I’m trying to see if it’s a physical problem (tube is a tight fit at the head so not sure if it’s going in all the way) or it’s a battery problem.

Thanks everyone!

[NutSAK]

My question is that ‘will it work?’ Does can a light powered by a single 10440 be replaced with 3pcs AAA?

I tried it but it didn’t light up so I’m trying to see if it’s a physical problem (tube is a tight fit at the head so not sure if it’s going in all the way) or it’s a battery problem.

Thanks everyone!

Yes, it typically can, electrically.  A 10440 Li-ion cell is 3.7 volts nominal, 4.2 volts max.  AAA cells range from 1.4 volts (NiMH) to 1.8 volts (Lithium).  3xAAA in series would be in the range of 4.2 volts to 5.4 volts, so similar to the voltage of the single Li-Ion cell.

[NutSAK]

I understand alkalines are widely disparaged and shunned among the torch fanboy community, being known as alkaleaks for obvious reasons.
I actually only have a few torches for which I use alkalines, one being an original E12 because it doesn't take any other, and two being Maglites that I've had since the early 90s and that come with memories. I usually use the el-cheapo multipacks from IKEA, again just because.

The original E12 works with Alkaline or NiMH.  Much better runtimes and no leakage are achieved with NiMH, and they're cheaper in the long run.

[Tasky]

The original E12 works with Alkaline or NiMH.  Much better runtimes and no leakage are achieved with NiMH, and they're cheaper in the long run.

This is true, but NiMH cells are not as commonly found when out and about, and will usually need charging when first purchased... whereas alkaleaks are sold all over the place and are an instant swap-out.
The only way for NiMH to be as viable is if you also have portable charging, such as a car adapter or a solar kit, but this then adds bulk in your load-carrying equipment.

[Zephon]

Thanks for the replies!

I finally made the flashlight work — the extension tube’s top wasn’t making contact with the head’s circuitboard surface (to close the circuit?).  In my first 2 attempts, I would stop when it was too tight.  What I did this morning was use a Cobra XS and a microfiber towel wrapped on the switch end of the Frog and turned until it stopped, then popped in 3x AAA newly opened alkalines.  I got the 2 blinks to show it was working!

Why am I going thru all this effort (and money) for this torch?  Well, I want “options”.  Alkaline batteries can easily be bought or brought and while having a charger for 1 or more 10440 cells is the ideal scenario, finding a place to charge it (even solar charging) feels more of a hassle than just re-loading new alkalines.  It’s more expensive no doubt.

I live in a tropical country where a storm or whatever can cause a power outage for possibly extended periods.  Hence, I need options.

Thanks everyone! 

[NutSAK]

This is true, but NiMH cells are not as commonly found when out and about, and will usually need charging when first purchased... whereas alkaleaks are sold all over the place and are an instant swap-out.
The only way for NiMH to be as viable is if you also have portable charging, such as a car adapter or a solar kit, but this then adds bulk in your load-carrying equipment.

My response was simply to your comment that the E12 only works on alkalines, which isn't the case. 

What cell you choose to use and why you choose them of course depends on your use case, which differs from mine.  I'm never in a position where I need the convenience of purchasing cells when "out and about", so I value quality cells over alkalines.  During an extended emergency, I would rather depend on a stash of lithium cells and my ability to find an energy source to charge NiMH and Li-ion cells than a store's ability to keep a high-demand item like AA alkaline in stock.

[Zephon]

I’ve got a curious question here:

16340 versus 18350

What’s the difference? I noticed that well, on my side of the world, it’s easier to buy a flashlight set with a bundled 16340. The 18350s are usually just ‘an afterthought’ in a light that comes with a 18650 battery. Size-wise, use-wise, cost-wise, is an 18350 worth more than the convenience of a 16340?

It’s just for casual use and not like my life would depend on how long or bright the flashlight would be.

[NutSAK]

The difference is that the 18350 is larger (18mm diameter vs. 16mm diameter) and offers higher stored energy.