NiMH vs Lithium-Ion batteries

Could you experts please enlighten me on the differences between NiMH and
Lithium-Ion batteries? For example, why does the Canon PowerShot A-series use
NiMH batteries, but the Canon PowerShot SD-series use Lithium-Ion batteries?

Will lithium-ion batteries eventually replace NiMH batteries? Or will both
types continue to be used well into the future?

 

Li ion batteries can be made in arbitrary shapes while NiMH batteries
are usually cylindrical. In the SD series, the thin rectangular
battery helps make the camera smaller. Li ion batteries also
weigh a lot less than NiMH batteries for the same amount of stored
energy.

A lot of the time, though, the advantages of li ion aren't that
important, and manufacturers use specially made incompatible li ion
batteries in order to sell additional expensive stuff to the customer.
There is finally starting to be a backlash against that. A couple of
years ago, most digicams used proprietary batteries and needed. Now
most of the manufacturers have cameras like the Powershot A-series
that use AA's, and customers understand why they benefit from that
(able to use the same NiMH batteries and chargers in several cameras,
etc).

I hope not, at least under the current scam.

Yes, probably.

 

They both have advantages and disadvantages, most of which are listed
in the post above. I don't see any "scam" here. Li ion batteries
usually cost more initially because they're lighter and hold a bigger
charge. The camera companies charge more for them because they're made
to fit the camera, and they can get away with it. When you consider the
overall cost of a new digital camera and all the accessories needed,
batteries, charger, memory card, card reader, etc., it isn't very much.
And if it's a reasonably popular camera, a replacement battery will be
available within months of the camera's release into the market at a
much lower price.
When I bought my new camera a couple of months ago, I researched the
battery question carefully. I came to the conclusion that I didn't care
whether the camera I bought used AA (standard size) or a proprietary Li
Ion battery, the cost would be roughly the same, after I bought the
batteries, recharger, etc. Most of the cameras that come with
proprietary batteries, usually Li ion, come with a recharger. If you
buy a second battery, which is a good idea, you don't have to buy a
recharger, unless you need to recharge outside the camera. Whey you buy
the rechargeable AA's or AAA's, you have to buy a recharger. While
cheap ones are out there, I heard enough horror stories here about the
cheap ones that I srpung some extra cash to get a high quality charger.
So it cost me more than a second Li ion battery would have cost even at
inflated dealer prices.
The only serious advantage of the NiMH's in standard sizes is that in a
serious bind, with no charged batteries handy, you can run to the store
and get Alkalines to get you through. Expensive, considering how long
they'll last in a digicam, but will get you the pix.
If you do a little online research and figure out how much the standard
size NiMH batteries and charger will cost, then compare it to the cost
of a spare Li Ion for a particular camera, you can make an intelligent
choice based on your own needs.
Hope this helps in your world.

 

That "much lower price" won't come anywhere near the $8.50 for a set
of 4 2300 MaH AA NiMH cells. And I'll still have an additional
charger to haul around. And that charger may well not be
international, and very probably doesn't work from a car lighter
plug (all of which my existing NiMH charger already handles).

And that battery may not be available *late* in the life of the
camera; they may have stopped producing it due to low demand. In
which case being unable to get a new battery (or a replacement
charger) may be what forces end of life for the camera.

As to cost, it depends. For a Fuji F10 at $320, paying an additional
$35 for another battery is about 10%. Doing that *every three years*
(which I hear is the average life of a Lion bettery) adds up over the
life of a camera even higher.

All of which means I may well end up buying a Canon A610 instead, and
sarificing the low-light performance of the Fuji F10. (The memory
card format is also somewhat of an issue, but *neither one* supports
compact flash, and neither does any other decent competitor. So I'll
spend probably as much as the camera costs buying new memory media in
some new format, and have to carry both around (all pro-level cameras
use CF, and look to continue to do so for the forseeable future
because there's no reason not to; the size isn't an issue in a DSLR,
and the capacity is important)).

 

I do. Most manufacturer-supplied Li ion batteries are way overpriced.

One thing nobody has mentioned so far is that NiMH batteries have
a higher self-discharge rate than Li ion batteries. So if you go for
long periods without using your camera, it's best to get Li ion.

 

You've just outlined the scam, such as it is. Were the camera makers
thinking, "We can force people to buy expensive batteries from us,"
when they went to proprietary batteries? It most likely occurred to
them. Fortunately for customers, the market is fairly good at filling
voids like that with less expensive replacements.

All this frenzy over smart chargers is amusing. I use two dumb-as-a-
rock chargers hooked up to a timer that's set to turn on for 1/2 hour
a day. I have three sets of batteries. One's always in the camera,
and the other two are normally getting trickle-charged in the chargers.
When I go off on a shoot, the charged spares go in the bag. When I come
back the depleted batteries go in the chargers with the timer set to 18
hours. (Approximately a full charge for these cells and these
chargers.) Once things are back to steady-state, I'm back to two sets
being trickle-charged and one in the camera. It's so dumb, it's
incapable of producing a horror story.

Yup. Even figuring that Li ion batteries die in three years or so
regardless of use, the cost of batteries is a small factor in a camera
decision. I prefer AA's, but the camera I'm pinin' for uses a

As do I.

Paul Allen

 

So many tradeoffs! The self-discharge problem is avoided by keeping
your spares on a trickle charge. The batteries in the camera may
discharge by the next time you use it, but the spares are always
fresh. And Li ion batteries self-degrade over time even when they're
not being used. Which is worse? A battery that predictably loses 1%
of its charge per day, or one that degrades to the point of unusability
after a few years? I dunno. I think the quality of the glass and the
ease with which I can get the camera to take the picture I see are
more important than the power source.

Paul Allen

 

brainlessly trolls:

Why not just google up the answer in a few moments?

www.google.com: NiMH lithium ion

Quickly reveals:

http://en.wikipedia.org/wiki/NiMH
http://en.wikipedia.org/wiki/Lithium_ion_battery

 

I skipped replying to your other message where you suggested
trickle charging NiMH batteries. Actually (and I think I got this
from some battery manufacturer's white paper, not sure of the
source, possibly Energizer) trickle charging is fine for NiCD
batteries, but not good for NiMH, so many NiMH chargers don't
trickle charge. But I do use your timer trick to keep some
appliance chargers going, though with two 1/2 hour charges/day.

I use enough AA NiMH batteries in devices other than cameras so if
I need a freshly charged set I usually have one or two available
that were charged no more than a few days earlier. I normally use a
fairly slow "smart" charger (more than 4 hours), but if I were to
quickly need a charged set but none were available, I also have a 30
minute charger, so the low discharge rate advantage of lithium
rechargeables isn't as significant as it might have been years
earlier when the time required to charge NiCD and NiMH batteries was
much greater. As many people here are aware, there are also several
15 minute chargers available, so it's not like the bad old days when
many chargers needed 13 hours (or more) to finish charging, and if
you needed to charger two sets of batteries . . .

You've avoided the biggest risk, having a temporary power failure
while using fairly fast, high current "dumb" (timer based) chargers.
And even with those, horror stories wouldn't be very likely. Just a
slight reduction (possibly not even noticeable) in the battery
capacity. The horror stories are greatly overrated, but assuming
the worst, since they're only NiMH, it'll only cost a few dollars to
get a new set, and a set that's probably higher capacity than the
ones they're replacing. The *real* horror stories (involving smoke,
flame and worse) almost always occur when recharging lithiums, and
fortunately, that's fairly rare.

 

Usually. But there's nothing that prevents NiMH or alkaline or
manganese or carbon zinc from assuming arbitrary shapes. Sony's
small, thin "gumstick" rechargeable batteries are available in both
NiMH and Lithium versions. Not replaceable, as their voltages are
quite different. I haven't examined the lithium versions closely,
but I assume (hope) they're constructed to make it impossible to be
inserted in equiplment that uses the NiMH gumsticks. And of course
the super thin batteries used in greeting cards for over a decade
weren't lithium. Caveat: another assumption.

Lithiums do weigh much less, but in such small cameras, the weight
of small non-lithium batteries would hardly be objectionable. My
old not-very-efficient Canon Powershot uses a battery pack
containing 3 AAA NiMh cells. Considering the great efficiency
improvements cameras have made in the intervening years, only two
AAA batteries would provide much greater battery life per charge in
a new, smaller camera. Two of these AAAs could fit in an extremely
small camera, wouldn't weigh very much, and I'd consider getting one
as long as it had some manual controls. But I wouldn't get any that
use lithium batteries, not because they'd cost more, although in the
long run the additional cost would be significant, but because
someday replacement batteries probably won't be available. I'm not
a big fan of planned obsolescence.

 

Whether it's inherent in the batteries or due to the protection
circuit, I'm not sure, but li ion batteries also self-discharge.
Leave you li ion powered digicam unused for a few months and you'll
need to recharge it.

 

Paul wrote:
All this frenzy over smart chargers is amusing. I use two dumb-as-a-
rock chargers...
Didn't realize I'd gotten "frenzied"!
For the price of your 2 "dumb as a rock" chargers and the timer, I got
a smart charger.

 

The NiMH versus Li-Ion Debate
-----------------------------
Manufacturers of cameras, camcorders, cell phones, PDAs, notebook
computers, high end bicycle lights, etc., moved from NiMH to Lithium-Ion
batteries for a number of very good reasons, but there are also some
advantages to the older technology, at least when the NiMH batteries
were AA or AAA size cells.


Advantages of Li-Ion Batteries/Disadvantages of NiMH batteries (AA/AAA)
-----------------------------------------------------------------------

Self-Discharge Rate
Li-Ion batteries have a self-discharge rate of between 1-3% per month
(when installed in a device, the self-discharge rate may be a little
higher). NiMH batteries have a self-discharge rate of between 40-50% per
month. For devices that are used only occasionally, NiMH batteries are
not a good choice, unless the device is always plugged in when not in use.

Energy Density
Li-Ion batteries have a much higher energy density. This means that you
can fit the same energy into a smaller space, or more energy into the
same size space.

Protection against Incorrect Insertion
Li-Ion battery packs are keyed to prevent insertion incorrectly (with
reverse polarity).

Li-Ion Batteries are more convenient to Swap and Charge
It is much easier to swap a single battery pack than to fumble with a
bunch of individual batteries. It is much more convenient to snap a
single battery pack into a charger than it is to insert individual cells.

Devices with Li-Ion Batteries are Usually More Reliable
The more battery contacts in a device, the less reliable it is. Battery
contacts get dirty. Spring loaded contacts suffer from metal fatigue.
Plastic battery doors that must put pressure against the batteries in
order for the batteries to make contact, eventually break.

Limited to Low-End Products (for Digital Cameras)
For the most part, only lower end digital cameras use AA batteries. The
manufacturer does this do save cost, since they do not have to supply a
rechargeable Li-Ion battery, or a charger, with the camera.

Of course for camcorders, cellular phones, PDAs, etc., there are no
longer many devices using NiMH batteries.


Disadvantages of Li-Ion Batteries/Advantages of NiMH Batteries (AA/AAA)
-----------------------------------------------------------------------

Li-Ion Batteries are Proprietary
Each manufacturer has its own battery pack design, and charges a lot of
money for extra packs. For the less popular products, there is no
incentive for third-party manufacturers to offer after-market batteries,
so the user must pay high prices for spare batteries. However,
after-market versions of the popular models of battery packs can be
purchased very inexpensively (see
http://www.sterlingtek.com/digital-camera-batteries.html).

Cannot Buy Proprietary Li-Ion Batteries in the Middle of Nowhere
For AA powered devices, if you are in the middle of nowhere and your
batteries go dead, you can get by with some AA alkaline cells. This is
somewhat valid, though this advantage is overstated. First of all, you
are much less likely to have your batteries go dead in the first place
if you are using Li-Ion batteries. Second, you can always charge your
batteries from any 12-15V source, including solar panels or a pack of
ten or twelve AA batteries. Third, for popular digital SLRs, the
optional battery grip can often use AA cells.

NiMH cells can be charged much faster
There are NiMH chargers that can fully charge four cells in 15-30
minutes. Fully charging the same capacity Li-Ion battery pack will take
several hours.


Myths About NiMH versus Li-Ion Batteries
----------------------------------------

NiMH cells are Cheaper than Li-Ion Batteries
This is only true in the rare cases when after-market Li-Ion packs are
unavailable. You can purchase very high quality NiMH batteries (i.e.
Panasonic or Sanyo) for around $2.25 each. So for a camera that uses
four AA batteries, you can have a replacement set for around $9. But
wait! I can purchase a replacement Li-Ion battery pack for a Canon S500
for $9. A replacement battery for a Canon digital SLR like the 20D is
$12. A battery for a Nikon D70 or D100 is $10.

You can purchase lower quality NiMH batteries for very low prices, often
around $1 each for 2000mA rated cells that have an actual capacity of
around 1800mA. These lower quality cells are usually sufficient,
especially with the faster chargers.

A Seperate Charger is Required for Each Li-Ion Battery or Li-Ion Powered
Device
This used to be a big issue, since someone with a PDA, cell phone,
digital camera, camcorder, etc., would have to carry around a charger
specific to each device. Fortunately, this is no longer an issue; there
are universal chargers available, that can charge nearly every type of
Li-Ion or NiMH battery. See
http://thomas-distributing.com/mh-c777plus.htm and
http://www.lenmar.com/plate_msc1u.asp.

 

So you think that the manufacturers of cameras, camcorders, cell phones,
notebook computers, etc., didn't expect that there would be a booming
business in after-market Li-Ion batteries, that would preclude them from
making a fortune in camera batteries?

 

That's a ridiculous exaggeration unless the nimh cell is defective.
3-5% a month is about typical for NiMH. In fact with the new Sanyo
Eneloop nimh cells, self-discharge is a few percent per YEAR.

Li ion self-discharges as well. Maybe not the raw cells, but all
consumer li ion packs contain a protection circuit which consumes some
power even while the pack is sitting. If you've ever left a digicam
unused for a few months you will have experienced the self-discharge
even with li ion cells.

Nonsense, just recharge it if needed.

False, crunch the numbers for yourself. Li ion uses roughly the same
amount of space as NiMH for the same amount of energy. What is true
is that the li ion cells holding that space WEIGH less than the
equivalent NiMH cells. Li ion can sometimes utilize space better
inside the camera since they're usually rectangular instead of
cylindrical. This mostly matters for the very smallest cameras.

I don't know of any NiMH consumer devices designed stupidly enough to
be damaged by reverse polarity. At worst you take the batteries out
and put them in again. Not that many users are stupid enough to be
unable to put the batteries in the right way either. And one can of
course always put the NiMH cells into a cartridge as is done with many
devices.

There is nothing that prevents putting removable cells into a battery
pack as is done all the time with NiMH packs. I have an Icom walkie
talkie which uses six AA cells in a holder that snaps onto the radio
just like a lithion ion pack pops into a camera. It's not rocket
science. The reason cameras usually don't use those is because the
benefits aren't great. Most people don't mind spending an extra 3
seconds at battery change time.

Yeah, tell that to the thousands of people with dead Ipods because
they couldn't easily replace the crapped out batteries.

Actually they are doing it because consumers are wising up to the
lithium ion scam and *demanding* AA-powered cameras. If you look at
digicam advertising of a year or so ago, they always touted li ion as
an advantage. If they used AA, they didn't mention it, or just listed
it factually. Now they list AA as an advantage.

Maybe there will be a backlash like there's been for digicams.

Let's not forgot also that you typically can't charge your lithium ion
packs AT ALL unless you have a separate charger for each one. I just
got back from a trip where I carried a digital audio recorder (Marantz
PMD660, AA powered), an MP3 player (Archos Jukebox, AA powered), a
laptop computer, a pocket digicam for snapshots (Nikon 3100, AA
powered), a bigger digicam for fancier shots (Olympus E-100RS, AA
powered), a cell phone for personal calls, and another cell phone for
business calls. That's maybe an above average amount of crap but not
extreme in the least. The laptop and the two cell phones were powered
by lithium ion (I couldn't find AA powered ones) EACH needed their own
charger. The other stuff, I carefully selected at purchase time to
use AA's. Result is I brought along a box of AA NiMH cells and ONE
fifteen minute charger and that was enough to keep all the AA stuff
running. The path of least resistance would have been to get an iPod
instead of the Archos, and lithium powered cameras instead of the
Nikon 3100 and Olympus. Three more battery types (one not removable
at all) and three more chargers. No thanks.

Let's go by the Energizer 2500 mAH cells which are $10 for 4 at K-mart
or Target. These are Sanyo HR-3U's with the Energizer logo, the best
cells you can get. 2600 mAH Sanyo cells supposedly exist but I don't
know where to buy them.

The S500's pack is 3.6 volts 1200 mAH which is 4.32 WH. That's the
equivalent of a little more than ONE of those 2500 mAH 1.2 volt AA
cells, not four. So replacing it would cost $2.50, not $9. (The
comparable AA camera would be something like an S400, which uses two
cells).

Dunno about Canon but Nikon just made sure that the D70/D100 battery
is incompatible with the D200. The D200 battery is physically the
same but has a hard-to-duplicate computer chip and costs $39.95.

And don't forget about spare packs. Suppose you shoot with an S500
and a D70. You need at least two D70 batteries in case one goes flat
while you're shooting. And you need at least two S500 batteries in
case one of THOSE goes flat. But having both go flat at the same time
is unusual, so if you have two AA-powered cameras, you need only one
set of spares since it will fit both cameras. Taking this to
conclusion, if you have ten different AA devices, just get one box of
identical NiMH cells and you have plenty of spares to power
everything. If you have ten different li devices you need separate
spares for them all.

Finally, it's easy to buy NiMH cells at local stores. Even my local
all night supermarket has them. Buying a D70 battery at a camera
store is $30 or $40. Buying them for $10 requires getting them from
some online mail order dealer and usually paying $5 or more postage,
having yet another transaction to keep track of, etc. And if you have
a few cell phones, laptops, etc., you find yourself having to buy
weird special batteries for them online all the time (I need a few
right now).

I think that's what you have to compare those $10 D70 packs to as
well. When I buy a pack like that, I'm happy if it works at all, but
I generally don't expect it to work as well as the manufacturer's
packs.

Those things are bulky to transport, slow to charge the batteries,
weigh a ton, and are a big pain in the neck to operate (you have to
put various clips and sensors onto the batteries). They're a pretty
distasteful alternative to using chargers designed for a specific
battery type, like AA's.

Conclusion: you're spouting li ion manufacturer propaganda. I wonder
what your interest is.

 

They do what they can to thwart the aftermarket. When an aftermarket
developed for Sony lithium packs, Sony made its camcorders not work
without the InfoLithium chip. That preserved their monopoly for
several years. Eventually the aftermarket apparently developed
compatible chips. Sony has been changing its battery form factor with
every new generation of camcorders since then, where it had previously
stuck with basically three sizes of battery (small, medium, large).

Nikon is doing the same. The D70/D100 battery will not work in the
D200 because the D200 insists that its battery have a special chip.

 

Oh yes, and these days, a Microtrack instead of the PMD660. That's
FOUR more chargers.

 

"NiMH batteries will self-discharge if left unused. Generally, within 30
to 60 days, batteries will become completely drained."

"http://www.thomas-distributing.com/maha-educate-batteries.htm"

Incorrect, see reference above.

The problem is that people expect to grab a device and have it work,
especially a device like a digital camera. They don't want to have to
wait two hours to charge the batteries.

This is due to poor design by Apple, not because of the batteries.

There has been no backlash in digital cameras. The low-end cameras use
AA cells, and the higher end cameras use Li-Ion batteries. What we have
seen is a huge increase in the number of low-end cameras. Cellular
phone, camcorder, and PDA users would never tolerate going back to NiMH
or Lead-Acid batteries because the drawbacks are so huge. The only
reason we still see some NiMH digital cameras is because they eliminate
the need for the manufacturer of the camera to include a battery and a
charger, which is a big savings when you're selling a sub-$200 camera.

Not true.

The S400 and the S500 use the same battery pack, so not sure what you're
trying to say.

You have a lot to learn. Nearly everything you wrote is completely wrong.

 

You can bet that an after-market battery will not be far behind. The
chip in the battery pack has a specific purpose, it's not there solely
to prevent after-market batteries.

I can use the same inexpensive Li-Ion batteries in my Canon G2, my Canon
20D, and my Canon camcorder. It's a much better solution than dealing
with a gazillion AA cells that self-discharge in 30 days.

 

They are wrong. I've used NiMH cells long enough to know this from
personal experience. See also the Eneloop cells:
http://www.letsgodigital.org/en/news/articles/story_5065.html

It is wrong. I've used NiMH cells long enough to know this from
personal experience.

1) have some charged cells on hand (much easier when your devices all
use the same batteries so you only need one kind); 2) use a 15 minute
charger; 3) you have to do the same thing with li ion batteries.

Every device using special batteries is susceptable to that, not just
non-removable ones.

Of course there has been. Look here on the ng, people care about this
much more now. Look at the ads and press releases that the
manufacturers run.

Cell phones, small camcorders, and PDA's are generally trying to get
in the tiniest packages that they can, so they use prismatic cells.
Although, if I knew where to buy an AA-powered cell phone I would do
so. Larger camcorders are expensive and cumbersome enough already
that people put up with specialized crap surrounding them.

Right, like the $180 vertical grip for the $1700 Nikon D200, which
takes eight AA cells.

You compared the cost of an S500 battery to the cost of four NiMH AA
cells, when the energy that the S500 battery contains is only equal to
about 1.4 of those cells.

You are the one who is completely wrong about almost everything. I've
had tons of lithium powered devices, I know exactly what their good
and bad points are, and I'm bloody sick of them and the rip-offs that
accompany them. It's unfeasible to avoid them totally but these days
I'm selecting AA devices whenever I can.