Home»Tech Guides»Why you should be using rechargeable batteries
Why use rechargeable batteries?
We’ve been using rechargeable batteries for decades now, and the benefits are amazing. Just four AA or AAA batteries easily can be used for five to ten years for us. Using rechargeable batteries and a charger can easily save thousands of dollars within a few years.
Instead of wasting hundreds of dollars over years on single-use alkaline batteries, you could just invest a little into just a few rechargeable nickle-cadmium (Ni-Cd) batteries and a battery charger that connects to a wall outlet (or through your computer via USB).
You will also need to spend a little bit of money into your electricity bills as well, but that cost is likely almost negligible compared to the overall cost of maintaining your household. We’re based in Canada, and our heating bills are crazy in winter!
To provide an analogy, the cost of charging batteries would be very similar to the cost of charging your phone every day. What’s the difference?!
It’s not like you’re going to stop using your phone anytime soon! (Though we do have fond memories of simpler times only having landline phones and faxes.)
So why not do a little bit of research to learn this life hack to save you hundreds to thousands of dollars in batteries?
Of course how much you save depends on how much you spend on batteries, but for us we use alarm clocks, remote controls, video game controllers, bluetooth, etc. which add up very quickly! It’s such a life-changer to be able to use everything wirelessly!
Are there chemical hazards to using rechargeable batteries?
Like anything in life, there are always risks. You will need to place your batteries into the charger after using them, but you should keep an eye on the charger while it’s charging. We’ve never heard of sparks flying from batteries!
But, let’s say if you do have a damaged battery, such as one that has its casing removed or maybe it got thrown around and is physically damaged. Putting such a damaged battery into a charger may cause problems.
In general though, keep an eye on the charger and plug it out if anything strange happens. As well, you should avoid leaving batteries charging for extended periods of times or unoccupied.
The batteries do become hot when charged for too long, and that can be a fire hazard.
These are just a small proportion of what happens when you charge batteries, to be honest we’ve seen people leave phones with cheap Chinese phone chargers at work overnight, which has caused a fire hazard.
Just take reasonable precautions when charging your batteries, don’t leave them for extended periods of time, and try to keep an eye on them!
What do I need to use rechargeable batteries?
All you need are the rechargeable batteries themselves and a charger! You will have to ask yourself what kinds of brands of batteries and charger are you looking to use?
The batteries you need
Batteries will come in different kinds. We mostly use AA and AAA batteries for the nature of our work. This is important because chargers are only compatible for certain kinds of batteries, and that is due to the varying physical dimensions of the batteries themselves.
You need to buy the rechargeable version of that battery instead of the regular (alkaline) version of the battery. Nowadays, it’s the nickle-cadmium (NiCd) or the nickle-metal hydride (NiMH) that are the popular type of rechargeable batteries.
You can’t go wrong with a big name brand like Energizer or Panasonic. AmazonBasics also has great deals on rechargeable batteries.
But really, you can’t go wrong with anyone, but if you do buy batteries from a smaller or unknown company, do keep an eyes on your batteries while they’re being charged!
What kind of charger are you looking for?
You also need a charger. In general, you can find easily two-in-one chargers that are compatible with both AA and AAA batteries. Also look for how many batteries can be charged in the device at once, usually it’s 4 batteries or 8 batteries.
“Trickle-charge” is a good keyword to look for when purchasing a battery charger, basically it will charge the battery at the same rate it depletes if you do leave the batteries charging for a long period of time, so that the net is zero. By doing this it helps retain the life of the battery instead of letting it deplete, then recharging it again, which is instead unhealthy for a battery’s life.
You can also look for chargers that have a display, some chargers will tell you a numerical estimate of the voltage in each battery and you can easily find which batteries are dead and cannot charge correctly.
Other charges may just have lights, red or green, to indicate if the battery is charging or if it has finished charging. Some even have sounds to indicate charging is finished.
The kind of plug it has is important as well. In general they use a 9 V power adapter that goes into your wall. You can also buy extensions to turn that so that you can plug it into a USB on your computer, if you want.
Some people buy a 9 V to cigarette lighter cable so that you can charge batteries in your car, though I suppose newer car models have USB ports and stuff?
Please consider sending a contribution to us here, we’re still driving a ’99 Honda Civic that has windows you need to manually wind down.
How do you find a battery charger with all these good features?! We can’t help but recommend chargers from La Cross Technology, we’ve been using the BC500 model since 2012, and at the time of writing this article it’s 2020.
They don’t sell that model anymore, but they have many newer models, upon which they keep improving their chargers more and more.
Why do we like these battery chargers? They implement trickle-charge. They only have 4 slots, but that’s generally reasonable unless you want to charge 8 batteries at once.
But for us, we can use four batteries and charge four batteries at the same time, then swap back-and-forth as necessary.
The display is amazing, and tells you the voltage for each battery. You can diagnose battery health from the voltage.
Sometimes batteries will stop charging properly when they’re many years old, but you can’t tell from its physical appearance unless you use a charger with a display or a separate battery tester device.
You can also tell from the number when your batteries are finished charging, so that you don’t leave them too charging long.
You would think that you could just memorize the time it takes to charge your batteries, but nope, over time it will take slightly longer, and some batteries will end up being healthier than other batteries in your pack. Sometimes you will use your group of batteries unevenly over years.
But don’t rechargeable batteries have a lower voltage?
Yes, rechargable batteries do have a lower voltage than one-use alkaline batteries, rechargeable batteries such a NiCd have a nominal voltage of 1.2 V, whereas alkaline batteries have 1.5 V.
If you have a display and use NiCd batteries, you can actually charge them to 110 to 115 % their actual charge, so even though their output is 1.2 V, we are able to charge them to 1.35 V or so on our charger, but that will affect the battery’s life slightly.
But even so, most technology will work fine because manufacturers know people are using rechargeable batteries, it’s not like the 90’s where they weren’t as often used.
If you want to read a more technical piece regarding how this works for rechargeable batteries, I strongly recommend reading some relevant publications on Science Direct.
What is battery voltage exactly? How do batteries discharge as they are used?
Putting it succinctly, voltage will tell you how long you can use the batteries. If you keep using them up, the battery voltage will go down.
Be careful though, voltage is not linear, it’s actually an exponential decay, see the link for a visual demonstration on what that kind of graph looks like.
It means that your battery will drain every quickly at first, then drain slower as time passes on until the battery is eventually fully discharged.
To give rough numbers, for an alkaline battery, 1.5 V is fully charged, 1.25 V would be about half charged, and 1.0 V is completely discharged. It doesn’t start from 0!
How do I store rechargeable batteries?
Just store your batteries in a normal room with normal temperature and humidity conditions. The way batteries are made nowadays is different than the old days, and condensation can damage the batteries.
You’re more likely to get worse performance or hazards from using damaged batteries.
There you have it!
So all you need are some rechargeable batteries, a charger, and somewhere to plug them in. Keep an eye on them as they’re being charged and don’t use batteries that are damaged.
Our technique is to use one group of batteries and always have another set of batteries charging. Then when the batteries we’re using have run out of juice, we swap them for the batteries that were previously charging. We keep repeating the process infinitely, it’s just like those old troll physics comics.
Sure, we will have to pay electricity for charging the batteries each time, but it’s about the same money you’d spend charging your phone each day or charging a laptop.
We live in Canada and our findings are those in line with developed countries, it is very possible you’re reading this in an area where your circumstances are different.
In the 90’s, we could easily go through a big pack of alkaline batteries in just a sitting, looking back it clearly was a big waste.
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