checking the microphone and webcam

Why do people claim rechargeable batteries can be used in anything?

Community QA

Add New Question Ask a Question 200 characters left Include your email address to get a message when this question is answered. Submit


Rechargeable Battery Construction

As with all batteries, rechargeable batteries consist of an anode, a cathode, and an electrolyte. During charging, the anode material is oxidized, producing electrons, and the cathode is reduced, consuming electrons.

Charging a batteryDiagram of charging a battery.
Charging a batteryDiagram of charging a battery.

These electrons constitute the current flow in the external circuit. The electrolyte may serve as a simple buffer for internal ion flow between the electrodes, as in lithium-ion and nickel-cadmium cells, or it may be an active participant in the electrochemical reaction, as in lead-acid cells.


Smoke alarms

Most alarm manufacturers recommend against using rechargeable batteries to power a smoke alarm. Smoke alarms that are not hard-wired into your home’s electrical system get power in one of two ways: a built-in battery designed to last up to 10 years, or a disposable 9-volt battery that you should replace once a year. No matter what kind of smoke alarms you have, according to the US Fire Administration, you should test the battery monthly and replace the entire device every 10 years.


Rechargeable batteries give you the convenience to just sit back and relax while you wait for your devices to be fully charged. You can even use USB rechargeable batteries anytime, anywhere for your convenience. This also keeps you from frequent visits to battery shops and changing batteries all the time.

These four things are the most important benefits of rechargeable batteries that you can never ignore. On the other hand, rechargeable ones have their limitations, too.

Tips for Using Rechargeable Batteries

  • Store in a cool dry place – These are the optimal conditions to store your batteries. Refrain from keeping them in the fridge or freezer as per the myth.

  • Don’t overcharge – Overcharging your batteries degrades the batteries faster and can mean that small amounts of power are leaked. This will result in the batteries not being fully charged when you come to use them. Some chargers have an inbuilt feature which stops charging once the batteries are full, but not all, and it is good practice not to rely on this feature. To avoid overcharging, it is recommended not to put batteries on charge overnight.

  • Don’t mix brands – Whilst you can charge batteries from different brands together, due to differences in power hold, it is not recommended to put a mixture of battery brands into a single device.

  • Recycle – Once again, do your bit to reduce landfill and ensure safe disposal by recycling your old batteries. Many supermarkets have battery recycling containers.

Charging Preparations

This part is an obvious one. Since you are using a rechargeable battery, you need to wait for it to be fully charged before using it on your devices, especially when going outdoors. This could be a hassle for some consumers so they prefer using disposable batteries instead.

Should You Switch to Rechargeable Batteries?

If you’re wondering whether or not it’s worth it for you personally to invest in rechargeable batteries, the short answer is most likely “yes.” Rechargeable batteries are almost always going to be cheaper over time. Even if you replace as few as four batteries each month, you’re still looking at a savings of $36.08-$62.48 over the course of five years. 

If you have kids who use batteries in their toys or if you have a battery-powered camera you use daily, know that the initial cost for rechargeable batteries will be significantly higher, but your savings over time will be even greater. Let’s say you do replace 10 batteries every month/120 every year. If you buy an eneloop charger with four rechargeable batteries plus an extra 12-pack, you’ll spend $61.72 the first year, but you’ll save $130.28-$196.28 over the course of five years.

Of course, you don’t have to use rechargeable batteries in all of your battery-powered electronics. If you have batteries in a wall clock or TV remote that you only have to replace once every year or two, it may be worth it for you to stick to the $0.32-$0.43 per battery cost as opposed to using a $3.33 rechargeable. Instead, you could save the rechargeable batteries for those devices that go through batteries like crazy: game console controllers, kids’ toys, cameras, etc.

How to get the most out of lithium ion batteries:

  • Don't fully discharge them — it shortens their lifespan.
  • Their chemistry doesn't work over about 45 degrees Celsius, and operating at high temp shortens their life.
  • If storing your device, charge it to about halfway before switching it off. Full charge puts stress on the electrode material.
  • Check the manufacture date when you buy them — they start losing capacity to hold charge from day one.

Matching the batteries to the charger

Different battery chargers are designed to work in different ways at different speeds, largely to suit different types of batteries. The first rule of battery charging is that a charger designed for one kind of battery may not be suitable for charging another: you can’t charge a cellphone with a car battery charger, but neither should you charge NiMH batteries with a nicad charger. Many modern rechargeable appliances and gadgets—such things as laptops, MP3 players, and cellphones—come with their own, special charger when you buy them, so you don’t have to worry about matching the charger to the battery. But if you buy a packet of generic, rechargeable batteries in a store, it’s important that you buy batteries that suit the charger you have or replace your charger accordingly. Note the voltage and current that the batteries require (it will be marked on the battery package or on the batteries themselves), be sure to choose a charger with the right voltage and current to go with them, and charge for the correct amount of time. If you want to buy yourself some rechargeable batteries but you’re not really sure how to go about matching batteries and charger, go for a combined set—where you buy batteries and charger in the same package.

Photo: Matching the battery to the charger. As the

Photo: Matching the battery to the charger. As the world shifts to more environmentally friendly battery-powered electric cars, we’ll need a lot more properly equipped, conveniently sited charging stations. This one uses photovoltaic solar cells (in the canopy) to charge the vehicles parked below. Photo by Dennis Schroeder courtesy of NREL.

Lithium-Ion Polymer Batteries

Lithium-ion polymer (LiPo) batteries are usually composed of several identical secondary cells in parallel to increase the discharge-current capability. They are often available in series “packs” to increase the total available voltage. Their primary distinction from lithium-ion batteries is that their lithium salt electrolyte is not held in an organic solvent. Instead, it is in a solid polymer composite, such as polyethylene oxide or polyacrylonitrile. The advantages of LiPo over the lithium-ion design include potentially lower cost of manufacture, adaptability to a wide variety of packaging shapes, reliability, and ruggedness. Their major disadvantage is that they hold less charge.

Top tips for better battery life

How can you get the best from your batteries? Here are some top tips I’ve found by reading through a variety of battery-expert websites:

  1. Rechargeable batteries work best when used regularly. Don’t leave them sitting around in your shed, fully charged or fully discharged for months.
  2. Battery experts suggest it’s a good idea to “condition” or “recondition” your batteries. This means you regularly let them discharge substantially before recharging if you can (though you don’t need to completely drain them).
  3. Match your charger to your batteries. For example, use an NiMH charger for NiMH batteries and be sure the charger uses appropriate voltage and current.
  4. Don’t overcharge your batteries. You will damage them.
  5. Don’t let your batteries get too hot or too cold, either during charging, storage, or use (it damages them). They will warm up during charging, but if they get really hot, something’s wrong.
  6. Don’t skimp on buying a decent, intelligent charger. Your batteries will last much longer if the charger treats them right!
  7. Wherever possible, follow the instructions that come with your appliance. For example, the instructions that come with the Roomba® robot vacuum cleaner tell you to leave it “docked” (sitting on its charger), trickle charging, all the time it’s not being used. If you don’t do this, you’ll find your Roomba loses its charge very quickly (even if you don’t use it) and you may well shorten the battery life.
  8. If you use something like a laptop, permanently plugged in, get into the habit of letting it run from the battery, perhaps once a week or so, until it discharges almost completely, to help keep the battery in good condition. You’ll find this helps to extend the life of your battery.

 Photo: Batteries come in all shapes and sizes. Yo

Photo: Batteries come in all shapes and sizes. You can’t always tell which are rechargeable just by looking. Of the ones shown here, only the nickel-cadmium and lithium-ion batteries can be recharged; the others are all single-use disposables. The large, silver-colored lithium-ion battery on the left comes from a laptop, while the smaller one (to its right) is from an iPod. The nickel-cadmium batteries are generic rechargeables that fit into a generic charger, such as the one in our very top photo.

Other Rechargeable Batteries We Reviewed

When conducting our research, we reviewed a large number of rechargeable battery brands.

In addition to our top picks, below are some of the other batteries that you could consider buying to fulfil your battery-powered needs.

The batteries are organised by brand rather than by type (AA or AAA).

Lithium batteries dont age gracefully

From the moment they're made, lithium ion batteries start losing their ability to store charge and generate a voltage over time. It's called ageing, and it happens whether they're being used or not, so check the date of manufacture when you buy a lithium ion battery.

The ageing is caused by chemical changes at the electrodes. The positive electrode isn't a solid lump — it's made of microscopic particles of a lithium-based material. Over time those particles coalesce together forming bigger lumps, so there's less surface area for the lithium-releasing reaction when the battery is being used (discharging).

And recharging doesn't send 100 per cent of the lithium ions back to the negative electrode — some ions always get permanently stuck to the positive electrode. So over time there are fewer positive lithium ions 'in play' in the battery.

About This Article

wikiHow is a “wiki,” similar to Wikipedia, which means that many of our articles are co-written by multiple authors. To create this article, volunteer authors worked to edit and improve it over time. This article has been viewed 36,705 times. 92 votes – 81% Co-authors: 8 Updated: February 12, 2022 Views: 36,705 Categories: Shopping

Thanks to all authors for creating a page that has been read 36,705 times.