How To Recharge Lithium Ion, Nickel Cadmium And Nickel Metal Hydride Batteries
Rechargeable Batteries: Don't know your lithium-ion from your nickel-cadmium?
Li-Ion, Ni-Cd and Ni-MH?
"Aaaagggghhhh!", I hear you say, "What Do All Those Symbols Mean?"
Before you run away, give me a moment to explain:
There are lots of websites out there explaining all about batteries.
They tell you all kinds of things about them and go into great detail about scary-sounding technical subjects like "memory effects".
But you don't really want to know all that do you?
You don't need to know the why, you just need to know the how.
All you want to know is:
- Which batteries are rechargeable?
- How often do I need to charge them?
...and this article will tell you just that: no more, no less.
Oh sure, if you want the low down and really, really need to know the whys and wherefores then I'll give you some links to further reading at the end.
Otherwise, hold onto your hats and read on!
Oh, and look out for the giraffe (yes, there really is a giraffe in this article, see if you can find it)
Photo credit: all photos mine, unless stated otherwise.
Plain old AA size: just the right size right to keep those little rabbits going (remember them?)
3 Kinds Of Rechargeable Battery
Well ok, there are more kinds, but these are the main ones that real people (like you and me) actually use!
Here they are, in order from least, to most used:
- Nickel-Cadmium (Ni-Cd)
- Nickel-Metal Hydride (Ni-MH)
- Lithium-Ion (Li or Li-ion)
How To Charge Them
There are different kinds of chargers you can get and they can look quite different to each other.
However, they all follow the same basic process:
- Use the right charger for the type of battery
- Put the batteries in the charger
- Wait until the light comes on/goes off, or whatever the instructions on the charger tell you
Note that you must put the batteries into the charger, you must insert them the right way round, just as you would when placing them into your favourite device.
Tip: most chargers have an automatic cut-off that stops charging the batteries when they are "full".
However, check the instructions for this feature before you leave it on all night.
Warning: Only recharge batteries that are specifically sold and labelled as "rechargeable".
Do not attempt to recharge standard alkali batteries as they can explode!
Photo right: my multi-purpose charger. Does both Ni-Cd and Ni-MH, in various sizes, all in one unit.
That's probably overkill for most people, but if you're trying to keep a green home, then it's well worth it.
More AA rechargeables, but may be cheaper ...or not, depending on the day.
Seriously though, it's worth shopping around, because prices for the different brands do go up and down.
Nickel-Cadmium and Nickel-Metal Hydride
These are usually found in standard sizes such as AA and AAA.
They look just like standard 'Alkali' batteries, but are labelled with their type (Ni-CD or Ni-MH) and will always be clearly labelled 'rechargeable'.
Below are some of my Ni-MH batteries, as an example. Pretty, aren't they?
A few years ago, Nickel-Cadmium batteries were all the rage, but Nickel-Metal Hydride are better and so you are more likely to find them in the shops these days.
Regardless of which you have, they operate best and last longest if you drain them completely each time before you recharge them.
Tip: if you use these in a high power item like a camera, keep an extra pre-charged set with you.
That way, when the first lot loses power you just swap them over, so you don't have to lug the charger round with you.
Don't Try This At Home - Poll
9V Battery Poll
Go on, we've all done it haven't we?
...Or have we???
You're in school or college and the teacher puts one of those rectangular 9 volt battery in front of you.
Now you have a chance to see what it's like to create a short, by placing your tongue against both terminals....
Have you ever put your tongue on the battery contacts to see what would happen?
Much neater than my old charger (see above) and still charges the most common sizes.
These are currently the "best" kind of rechargeable battery you can get.
Li-ion batteries hold more charge - and for a longer time - than other kinds, and you can more or less do what you want with them.
They're much better for high power items too, like digital cameras with a built in flash.
They have become extremely popular as a result and come in all shapes and sizes as they are often custom built for a particular device.
You probably have one in your pocket right now, as most mobile phones have them inside.
Unfortunately, you can't get them in standard sizes (AA, AAA, etc), so you won't be able to put them in your old Ni-CD/Ni-MH charger either.
Apart from phones, examples of devices which can have Li-ion inside are iPods, tablets and laptops.
Not all cameras do, so check before buying - if it still uses Ni-MH batteries, then it could be the reason a particular model is really cheap.
Important: Lithium ion cells are not like Ni-CD or Ni-MH batteries!
You can charge Li-ion as often as you like and they last longest if you:
- Use them a little bit and then charge them (even once a day is fine)
- Don't let them drain completely (but see below)*
- Don't overcharge them by leaving them plugged in for long periods once they are at 100%
The long and the short of it, is that if you are shopping for a new gadget or device that uses batteries, get the model which has a lithium-ion battery, if you can.
Tip: If you are not going to use a Li-ion battery for a long time (weeks or months) then it is recommended that you store them approximately 40% charged.
*Tip: most devices, like phones, have an indicator showing you the current charge state.
However, sometimes they can lose their calibration and give funny readings for the battery (one minute appearing to be 'charged' and the next, low or empty.
If this happens, simply use the battery until the phone says "empty" or "low" before you recharge it fully.
This full recharge will recalibrate the battery and should give the phone better readings again.
AAA size, but a 12 pack to keep more of your devices going, for longer.
All batteries die eventually, but if you treat them right, they should give you years of good service.
For Those Who Really Want To Know
Here's some web sites that will tell you why rechargeable batteries are the way they are.
For the technically minded or the curious.
- Battery charger - Wikipedia, the free encyclopedia
Wikipedia article with a good overview of different kinds of charging technologies.
- Frequently Asked Questions on How to Charge Batteries
FAQ arranged in a nice, simple table.
- How Often Should I Charge My Gadget's Battery to Prolong Its Lifespan?
Great Lifehacker article (aren't they all?) hitting the nail on the head as far as lithium-ion battery care is concerned.
Leave A Comment
Enjoy this post, or find it helpful?
I think we have some very "interesting" results from our poll "would you put your tongue on a battery": what do you think?
Then let us know.
© 2013 Tim Bader