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View Full Version : Are NiMH as good as we think?



Geoff Chandler
01-25-2005, 01:13 PM
I use NiMH in my Olympus and I am very happy with them I have two pairs of 2100mAh and and two pairs of 2300mAh the latter are Jessops and last a bit longer as expected.
I also have a spair extra pair of 2100's (sorry I'll get to the point soon!!) and recently bought the kids a CD walkman each and got them 200mAh's for them (that's all I could get at the time). My son found his walkman ran out much sooner than expected - well I have recharged them and well see if it was because they were new (maybe?) My extra 2100's are used in a Neon flashy lamp on my pushbike & they don't seem to last as long as the Alkaline rechargeables, and nowhere near as long as non re-chargeables. Hey! - do these batteries believe that they are only to work best in cameras??
Any comments??

Geoff

David Metsky
01-25-2005, 02:01 PM
Different types of power usage require different types of batteries. NiMH are great for high peak load, IIRC, like with a digital camera. CD players are steady drain, a much different load pattern. It doesn't surprise me that Alkalines work better in CD players.

Rhys
01-25-2005, 02:01 PM
I use NiMH in my Olympus and I am very happy with them I have two pairs of 2100mAh and and two pairs of 2300mAh the latter are Jessops and last a bit longer as expected.
I also have a spair extra pair of 2100's (sorry I'll get to the point soon!!) and recently bought the kids a CD walkman each and got them 200mAh's for them (that's all I could get at the time). My son found his walkman ran out much sooner than expected - well I have recharged them and well see if it was because they were new (maybe?) My extra 2100's are used in a Neon flashy lamp on my pushbike & they don't seem to last as long as the Alkaline rechargeables, and nowhere near as long as non re-chargeables. Hey! - do these batteries believe that they are only to work best in cameras??
Any comments??

Geoff

Oddly enough... I bought some Jessops alkalines, some 20 years ago and they still work. I use them in my radio (which I use occasionally) and they're as good as new.

I do find a difference between rechargables. I bought some cheap rechargables in a K-Mart and they are awful. My GP 2100s will run rings around them yet they're supposed to be the same capaity.

I do realise that some batteries are better for some uses. For example NiMh and NiCad are both designed for high-drain appliances rather than low-drain and both have quite high self-loss.

A rechargable would power, for example, a clock but would lose its charge before the end of three months. An alkaline works better in those circumstances.

I do remember people using NiCads to power their walkmans, in college. I also remember they needed several sets during the day. I think NiMh is better but I suspect there can be a wide variation. Perhaps, like NiCads, they need to be conditioned before use?

CameraNewbie
01-25-2005, 09:00 PM
ok i have my eyes set on another model. Canon SD300, wow, 2.0''LCD!!! WOW

I can get it for $300 cdn!!! Brand new! Looks much smaller too than A series!

Rex914
01-25-2005, 09:16 PM
Uh, wrong thread replied to?

As people have already said, it all depends on the device being used. Optical drives like CD players don't expend much power but they do it constantly. Digital Cameras and other high tech devices expend a lot of power, but they do so in shorter bursts. That's why nimh and li-on batteries are used in digital cameras, laptops, anything that expends tons of power. If you've ever used plain AA batteries in a digital camera, Game Boy, you'll notice that the batteries go "low" earlier than normal and the performance of the device actually drops because it's like a tired animal that can't go any further.

Geoff Chandler
01-26-2005, 01:04 AM
Thanks Guys
Between you all I reckon that neatly explains it - I concur - I also used a NiMH in a clock and it lasted about 2 months if that - whereas a normal battery would last at least a year.
Keep the NiMH for the cameras then.
Geoff

Alnath
01-26-2005, 08:09 AM
It is still cheaper to recharge them than buy new alkalines though, even with more charges needed its still cheaper, i use 2 1500mAh ones in an MP3 CD player and they last around 20 hours.

Rhys
01-26-2005, 10:56 AM
It is still cheaper to recharge them than buy new alkalines though, even with more charges needed its still cheaper, i use 2 1500mAh ones in an MP3 CD player and they last around 20 hours.

I agree. I'd never use a rechargable in a clock though. Having to replace clock batteries every 2 months is as boring as having to wind a watch every day.

D70FAN
01-26-2005, 03:25 PM
Thanks Guys
Between you all I reckon that neatly explains it - I concur - I also used a NiMH in a clock and it lasted about 2 months if that - whereas a normal battery would last at least a year.
Keep the NiMH for the cameras then.
Geoff

The main reason that you had to replace the clock batteries every 2 months is that the self-discharge time for NiMH cells is about 45 days. It is one of the irritating characteristics of NiMH (and NiCd).

I was using rechargable NiMH AAA's in my Handspring, GPS, and MP3 player. If I forgot to change them monthly, in the handspring and GPS, I would loose my data base and have to reload from my PC. A real pisser when you are on the phone looking for info and the PDA is dead. Or lost and the GPS is dead.

So now I use Lithiums, for critical applications, which have a very low self discharge rate (10 years), and have 5 times the usable power of alkalines. Oh, and they are lighter.

They run about $10 for a set of four, but I only have to replace them once every year or two.

Alkaline and Lithium, non rechargables, have a shelf life of many years and rechargable LiIon's can go 6+ months and still work ok.

NiMH's are great for digital cameras, if you shoot a lot of pictures every month and go through batteries quickly. But you may want to keep a set of Lithiums in your bag for emergencies....when you forget to recharge your spare set of NiMH's. ;)

Rhys
01-26-2005, 04:35 PM
I took my mobile phone with me to America. That has a lithium battery. What with the different mobile phone network out there and the different power supply with its bizarre plugs, I never could use it there or charge it. When I returned some 3 months later to Britain, my phone still had sufficient charge in the LIon battery to make about 20 minutes of calls. Not bad for something that hadn't been charged for 3 months.

I'd say that if it wasn't for consumer electronics like mobile phones and digital cameras, battery technology would still be stuck at NiCad and zinc-carbon batteries. Battery technology has leapt forward in the last 10 years more than it ever did in the previous 100.

Alnath
01-31-2005, 06:19 AM
I agree. I'd never use a rechargable in a clock though. Having to replace clock batteries every 2 months is as boring as having to wind a watch every day.

Thats down to the fact that Ni-Mh self discharge really quick, mine go flat in a week if just left to stand.

Newbie
01-31-2005, 06:34 AM
As other people mentionned NiMH are the best for certain applications. In a digital camera, it works like a charm, in a discman, it should do good provided that it is used often. Keep in mind that NiMH batteries need 3-5 charge cycles to reach their maximal capacity, for example, in my A95, I could take about between 209 and 284 shots with new batteries on their first use. Now, after 4 cycles, I am at 409(over a period of 1 month). Flash usage remained constant and LCD is used all the time. So, yes it is true that the quality of the battery is important, but so is the quality of the charger.

I see that you've got rechargeable alkines, so I presume you also got a charger for those. Those batteries would totally suck in a digital camera, but will work great in your clock, in a tv command. I do not own any of these, but I might when I will need to(for environmental reasons), but if I'm not mistaken, they are worst at their 1st charge and get better everytime you charge them.

Geoff Chandler
02-01-2005, 01:46 PM
[QUOTE=George Riehm]The main reason that you had to replace the clock batteries every 2 months is that the self-discharge time for NiMH cells is about 45 days. It is one of the irritating characteristics of NiMH (and NiCd).

I didn't know THAT either - This is a useful Forum
Thanks
Geoff

gary_hendricks
02-20-2005, 03:12 AM
Different types of power usage require different types of batteries. NiMH are great for high peak load, IIRC, like with a digital camera. CD players are steady drain, a much different load pattern. It doesn't surprise me that Alkalines work better in CD players.

NiMH are best for digital cameras.

Geoff Chandler
02-20-2005, 06:49 PM
Just think - all that wonderfull help and advice for no charge!! :D
Geoff

gschoen
03-12-2005, 03:58 PM
I use Ni-MH for most things in my house. They are the first rechargable battery technology that has alkaline power (better than) and hold their charge a decent amount of time. I use them in:

*Frequently used remote controls, esp. w/ backlight (Usually alkalines only last me 3 months anyway, Ni-MH have lasted even longer)
*Frequently used flashlights (my bike lights and small flashlight to see behind TV & Receiver)
*MP3 Player (was going through an alkaline every 3-4 gym trips. NI-MH lastes weeks)
*CD Player (Everyone knows how many alkalines a portable CD player eats!)

What I do NOT recommend using them for:

*Backup/Emergency Flashlights (Who wants to change batteries when your power is out? Who can even find the batteries?!? )
*Infrequently used/backup remotes (For instance, if you have an all in one remote and the originals sit in a drawer. Use alkaline or leave them empty and add batteries as needed.)
*Safety Devices, smoke detectors, CO Detector, etc. (Obvious reasons.. a long lived battery helps minimize downtime)
*Anything you might stick in the closet and forget (Toys, etc. They're too expensive for this and can be damanged by too infrequent use)
*Something that performs better with a full 1.5V (I have an RF remote that does better when batteries are at higher voltage. I use Lithium AA's since they keep a high voltage for most of their life, unlike alkaline where voltage declines progressively with usage.)

I figure my using Ni-MH in some applications other than their "intended" use, I have not only saved a lot on batteries but taken a small chunk out of my personal waste stream. For my frequently used devices, even low power ones, I find battery changes to be the same or often less often than alkalines.