The Rechargeable Investment


Let me first begin this post by describing a problem that’s been plaguing modern families for decades. A problem that technology seems incapable of stopping.
What’s this nefarious issue that burns at the heart of our collective souls?
Every darn child’s toy requires batteries… and those toys burn through batteries faster than lightning. Yes, batteries!
Until you have kids, you’ll never understand how quickly a family can go through batteries. My boys must burn through 5-10 batteries a week. (They must be eating them…but appear to have suffered no ill effects)
Given the incredible frequency that kids go through batteries, keeping them in electronic ‘bleeps’ and ‘bloops’ ends-up being an incredibly expensive proposition. I mean — have you seen the OUTRAGEOUS prices stores charge for alkaline batteries these days? Prices can exceed $1.50 a battery. For just regular-old batteries! It’s insane.
Last time I bought alkaline batteries at a grocery store, I nearly passed-out right there in the checkout line. Somehow they get away with charging stoopid prices for batteries these days.
Thankfully, I’ve found a viable solution — One that doesn’t require me to take out a second mortgage to keep all of our electrical goods functioning.
A solution, that might just be the single best investment you can make this year.
Not Your Grandma’s Rechargeables
If you haven’t guessed already, today’s post is about the incredible wonder that is rechargeable batteries. But not just ANY rechargeables… most of ’em are not worth your time and effort.
The first generation of rechargeable batteries were first available to consumers in the 1980’s. They used a battery chemistry called Nickel Cadmium (NiCd) to work their rechargeable magic. But honestly, those first generation rechargeable batteries kind of sucked — they were expensive, capacities were terrible, and they wore out quickly. Cadmium is also a toxic heavy metal and must be recycled at dedicated facilities.
By the 1990’s a second generation of rechargeable battery chemistry had been invented, known as a Nickel-Metal Hydride battery (NiMH). This improved the rechargeable battery situation significantly — capacities and lifetimes improved. But, there was still one big major drawback — over time standard NiMH rechargeable batteries slowly discharged. Over time, they would eventually go dead and require recharging. This meant you couldn’t just leave a rechargeable in the device and expect it to stay charge.
This issue plagued Nickel-Metal Hydride batteries for over a decade, until 2005 when Sanyo developed the Low Self Discharge Nickel-Metal Hydride (LSD-NiMH). The battery was branded Eneloop, and in one fell swoop it destroyed any chance of me ever buying an alkaline battery again.
They’re that good!
In 2017, Eneloop batteries (now owned by Panasonic) are in their 5th generation. They’ve improved with each generation and now utterly crush the competition when it comes to batteries. I’ve tried numerous other brands, and none even come close to comparing with Eneloops. They’re reasonably priced, last longer, and perform better than all the rest. Believe it or not, these latest NiMH batteries now perform so well I will never buy another alkaline again.
Let me take you through the math…
Doing The Math
Obviously rechargeable batteries still bear the brunt of higher upfront costs, but this isn’t nearly as bad as it used to be. Eneloop’s 5th generation now cost about $2 per battery, and tout up to 2100 recharges before failure. At a minimum, 5th generation Eneloops are rated at 750 recharges before failure, and I believe it.
For example, please consider this Eneloop battery I’ve owned since 2008:


So what do the numbers look like when compared to other batteries? I popped on down to my local Costco to do some proper comparison shopping on AA batteries:
Costco’s prices can (sometimes) be cheaper than purchasing via Amazon. During my Costco visit, a 10 pack of AA batteries was $19.99. While I was there, I also grabbed comparison prices for both Duracell and Kirkland brand alkaline batteries:
The numbers are surprising. When compared over a lifetime, the rechargeable numbers look very good:
As long as you don’t need to purchase a battery charger (I have about 6), the cost per charge is a mere $0.0014 at the midpoint (1425 recharges).
But let’s say you’re skeptical, and choose to use the lower-end estimate for Eneloop batteries (750 recharges), that’s STILL only a cost per charge of $0.0027. Shockingly high isn’t it?
But what if you’re really pessimistic and don’t believe my claims about the reliability? Perhaps you believe you’ll only see 100 recharges out of a single battery…
Even with those really pessimistic numbers you’ll still be crushing the cheapest Kirkland brand alkaline batteries by an order of magnitude.
In fact, to merely break even on Eneloop batteries (versus the Kirkland brand alkalines), you’d only need to realize about 7 recharges. Yes, only 7.
That’s an easy proposition for a family that uses batteries as frequently as mine. More than likely you’ll do far better than just break even.
Hey, What About Power?
By now (if you’re still reading this), you’re probably wondering what’s missing from this equation — The energy required to recharge! That’s not free!
First off, we need to understand how much power is required to recharge a AA battery — Eneloops require about 2.8 watt hours per recharge (Recharge voltage of 1.4v for 2000mAh).
How much you pay varies depending on your local electricity rates. In my area we pay 11 cents per kilowatt hour. That results in a recharge cost of $0.000308 per charge. Practically a rounding error as far as the math is concerned.
Over the lifetime of a Eneloop battery (1000 recharge cycles), that would mean a cost of $0.308. That’s a tiny fraction of the overall savings realized from Eneloop rechargeable batteries.
Not Chump Change
Still not convinced? Let’s look at it a different way — Think about it in terms of investing. If you invest $20 and can realize those seven recharges in a year, you’ve broken-even in the first year.
By the second year, it’s a 100% return on investment for that year, and every year thereafter.
If you manage to keep your batteries for 10 years, you’re looking at 10 times your initial investment in savings. That’s $200! Yes, two hundred dollars saved from a pack of $20 batteries.
I would kill to see returns like that from my portfolio investments.
Lest you think this is some kind of joke, please realize that I’m on year 9 from many of my initial eneloop batteries (technically they’re second generation Eneloops). They really do last that long.
I don’t know about your household, but in my house $200 is not insignificant. Like all the other small things I do to save money, it adds up to significant savings. Over time, that savings was invested and grew into our $2.5 million net worth.
So do yourself (and the environment) a favor — stop buying alkaline batteries and start investing in Eneloops. You’d be foolish not to…
[Image Credit: Flickr]
You’ve convinced me. I’m buying some Eneloops today. We don’t have kids and don’t use many batteries but those are numbers are too good to ignore. I want to support this company.
Thanks for the insight, Mr. T!
We’ve tried some rechargeables. Don’t know the brand names, but I don’t think they were Eneloop. The ones I’ve bought couldn’t seem to hold a charge. The LSD batteries you describe would be best to power those flashbacks… er, I mean flashlights.
Cheers!
-PoF
I had the same problem with the other brands too. Eneloops are WAY better than anything else I’ve ever tried, aside from lithium ion batteries. But sadly, nobody makes rechargeable lithium ion batteries in the standard AA and AAA formats.
Thanks for the reminder! Mr. Picky Pincher has gotten me on board with rechargeable batteries. I’m not sure why I was ever resistant to the idea. It’s not much different than charging the battery on a phone. I want to try the Eneloop ones you suggest; I think we use Duracell and I know we could get something with more “oomph.” And I love avoiding the environmental consequences of tossing batteries. 🙂
Eneloops are great. Once you go blue, you never go back! 😉
Great analysis, Mr. Tako. Rechargeable batteries are definitely a good way to save for electronics that require them.
Hmm, I’ve been eyeing up Eneloop batteries for a while now but just haven’t pulled the trigger. In my head, I keep comparing them to the old-school rechargeables that we just Ok.
I think your post may be all I need to place an order!
— Jim
Jim @ Route To Retire recently posted…Long-Term Food Storage Needs to be Part of Your Plan
Do it. As long as you get genuine Eneloops, you won’t regret it. I would avoid most Ebay sellers and many of the 3rd party Amazon sellers…too many fakes out there.
Cool, I have a few chargers and NiMH batteries I’m still using. I’ll have to check out those LSD ones next time I need more.
Can you use a old NiMH charger or do you have to buy a proprietary charger?
I notice you did not do a scenario for the first-timer who has to buy a charger. Is that because the first battery is a loss leader and you need to have the sunk cost of the charger to start making the B/C ratio pencil out?
Any NiMH charger will work. I didn’t include a scenario for buying a charger because it makes the math too messy. The kits (which Costco and Amazon sell) include both AA and AAA batteries, as well as a charger. To keep things simple and understandable, I just stuck with AA batteries. No sense in confusing everybody.
That said, the cost of the charger is roughly $10. In that case, the payback period is an additional 3-4 charges (roughly).
What do you use for devices requiring 9 volt batteries?
Sadly, there isn’t a 9 volt rechargeable from Eneloop, but there are other brands.
I’ve been using Eneloop for my photography business for years. They are especially great for work that requires a flash or two. They hold charges well and are good when I’m firing the flash in quick sequences. We are using Eneloop for household electronics too.
I’m only using good traditional batteries for things like a beacon for backcountry skiing.
Nice write up. I don’t often use batteries but I’ll look for these next time I do.
Also, I am human or cephalopod.
I have never seen eneloop batteries before. Sounds good, though. Alkaline batteries just doesn’t cut it anymore. It’s better to pay the higher initial fee and reuse them.
Absolutely agree Joe! You should give Eneloops a try!
Your title made me wonder if you will talk about dividend investing. You buy a stock, it pays a dividend. Then it keeps paying that dividends for years to come. It is like a rechargeable money machine 😉
In my mind, the two are really similar! One is an investment to save money over time, the other is an investment to generate cash over time.
We long ago stopped replacing kids toy batteries. It helps our sanity as I can only listen to a toy sing so many times. We do heavily use rechargeable for cameras, remotes, and video game systems.. I never heard of this particular brand, I’ll give them a try the next time the rechargeable alkalis give it up.
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We tend to “rotate” toys for our kids. Bringing out ones they haven’t played with in awhile and putting away ones that have already been well loved. Usually we move batteries around at that time.
Ask around — Eneloops are the best!
We moved to the Enloop batteries about a year ago. After such great reviews by Steven Harris, we knew we had to give them a shot. Great price at Costco for a starter set and charger. I will say, that they don’t seem to last as long. I put them in our thermostat and normal batteries will hold up for months, while the Enloop will cause a low battery alarm in a few weeks. But, just a quick charge and we’re good to go. My wife came home with a few packs of Duracell the other day, and I about fell over when I saw the receipt. Looking forward to the continued improvements in these as new generations are introduced.
Geez, you know more about batteries than I do about anything 😛 I’ve never seen such a detail breakdown of the cost benefits of owning Eneloops before. Hell, I’ve never even heard of Eneloops until now. Will try them in the future. Good to know!
Sorry, my nerd was showing.