Saving Money on Smaller Batteries ("D" Cell and Smaller)

[308Mike]

This may or may not be common knowledge for most of you - I certainly wasn't aware of it nor knew it, OR had occasion to run across it in a manner to figure it out until just recently.

What I'm talking about is how devices use/drain batteries in consumer devices.

Due to my wife's sensitivity to light (most of our home windows are covered with aluminum foil, which has been a MAJOR plus in reducing our utility bills), I've resorted to using a headlamp in our home when she's highly sensitive to light (and sometimes the light triggers migraine headaches), so we tend to go through 'AAA' batteries at a pretty good rate.

Recently, I began testing the batteries coming out of the devices when I was ready to replace them and discovered that for the MOST PART, only ONE battery out of the series was drained to the point of replacement - the others were fine. So, now I test ALL my batteries coming out of my devices before replacing with fresh batteries, and this technique has drastically cut our consumption of batteries (rechargeable batteries don't last long and I'm CONTINUALLY putting replacement batteries in the charger - although I haven't implemented only replacing the battery that NEEDS replacing on the rechargeables yet).

BOTTOM LINE: Use a battery tester and ONLY replace those batteries which NEED replacing.

You might find you'll be spending MUCH LESS money on batteries when you start replacing ONLY those batteries that NEED replacing instead of doing like I used to - dumping ALL the batteries and replacing the lot of them each time the device declined in performance (with a head-lamp, you can drain them pretty damned far and still use it to read, etc., etc., before needing to replace the batteries). Out of three batteries, I've starting only replacing ONE AT A TIME, and not NEARLY at the same rate I had before.

So, if you use a lot of devices which require batteries, I suggest getting a hold of a good, EASY TO USE, battery tester (not necessarily a volt-meter, unless you use one all the time and are comfortable with it), but a simple Battery Tester - one you can ask your little sister to tell you what the needle says.

Use the battery tester, AND replace ONLY those batteries needing to be replaced, and you might discover you're saving a little chunk of money on a regular basis by replacing ONLY those batteries needing replacement.

YMMV - I've saved money doing this, and I hope you can too!!

[Rich Jordan]

From what I've read you do not want to do that with lithium batteries; alkalines may be ok. Mismatched lithiums can cause overheating and possible explosion if the device being powered draws enough.

I don't know if the NiMH rechargeables have the same issue but have you tried the Eneloop brand? We use them here in the AA dogwalker flashlights and they seem to last about as long as fresh name brand alkalines before needing recharge.

[308Mike]

Rich, you're absolutely right in the mixing of batteries, particularly in chargers!!

You should ONLY use one type at any time (alkaline with alkaline batteries, NiCads with Nicads, etc., etc.), DO NOT nix and match battery types (something I neglected to mention).

Even so, by using a battery tester to check your batteries before replacement, you might discover you only NEED to replace ONE battery instead of three (or four & more).

You will probably be surprised at your battery usage (and money saved) after performing such checks.

YMMV

[Rich Jordan]

I wasn't referring to mixing types, though that point is very well made. I was referring to mixing used (even if still good) with new lithiums in a device, particularly a high draw device like a high output flashlight. They can and will overheat and do bad things.

I save 'good used' lithiums from my two-cell CR123 light to use in a one-cell light; they never get used in the two-cell again. However most of the time, both CR123s have come down in voltage pretty uniformly.

The AAA and AA lithiums do wear down unevenly more often, but again, I have a couple of red LED single cell lights (the red is the most power efficient and will light up with batteries too low to power blue/white LEDs) so they don't get wasted.

[Termite]

I wasn't referring to mixing types, though that point is very well made. I was referring to mixing used (even if still good) with new lithiums in a device, particularly a high draw device like a high output flashlight. They can and will overheat and do bad things.

Oh yes, absolutely. I know from painful experience.

Years ago before I learned better, I had a 2 cell lithium flashlight that I only replaced one battery due to the battery failing(a no-name cheapy). The other used battery was at 30%. The new fresh battery overdrove the older battery into thermal runaway........in my pants pocket.

[308Mike]

I *just* checked the batteries (3 of them, AAA batteries), of my headlamp. Instead of the usual top battery being depleted, this time it was the middle battery. This only goes to show that you should ALWAYS check ALL the batteries when replacing and not assume the one you think might do it might not be the ONLY problem battery. After all, you still have whatever batteries are left, and even if you DO find an almost dead battery, it DOES NOT mean that is the ONLY battery needing replacement (much like a complacent cop who believes that once he's found the hidden knife/blade on a pat-down that he's found them all).

CHECK THEM ALL, and replace as necessary. But I bet you'll be surprised at just how many times you can get by only replacing ONE battery instead of them all (at least for a while).

And has been pointed out earlier, DO NOT mix battery types in devices (ESPECIALLY chargers)!!!!