Rechargeable batteries, power questions.

[friscuba]

This may have been covered earlier but I couldn't find it easily in a search.

I picked up a digital camera (Oly D-40)a little over a year ago and picked up some 1600mA rechargeables at the time. Now I'm seeing 2200mA and 2300mA batteries are out there....

Is there any risk of a battery's power being too high? Is the number an actual output, or is the output constant and the higher number indicates an increase in power "storage" ability and the ability for it to last longer. I'd hate to put something in which the camera can't actually handle....better to check before finding out the hard way.

Also, how much of a difference are people seeing when upgrading batteries as far as the number of pics they can take. Does a 10% increase in mA rating indicative of an ability to take 10% extra pictures, or is it greater in practice?

Thanks for any input.

Steve

 

[Dee]

When I got my camera, the 1500mAh batteries had just come out so I used them for almost a year. I was lucky to get 2 dives out of them.

My latest batteries are 2200mAh and I can tell an appreciatable difference. I'm still in the process of getting them cycled but with only 3 full charges, they are giving me 2 full dives with plenty of juice left over for viewing the pictures, changing settings, etc. I expect to get 3 dives easy our of them once cycled.

I can't give you percentages and all that technical info you guys like, I just know they ARE lasting longer and the write times seem faster, although that may be my imagination!

I haven't heard anything about there being a limit on the power of batteries to be used.

 

[MonkSeal]

friscuba once bubbled...
Is there any risk of a battery's power being too high?

This is a capacity of batteries meaning how long it can operate giving specified output voltage.

E.g. 2000 mAh means that battery can supply 2000 mA current during one hour i.e. if your device has consumption 1000 mA battery will last for two hours. During this time output voltage is constant (or near constant which depends on quality of battery).

So, if you "upgrade" your batteries your camera will operate longer time without changing batteries. Is this 10% of time for 10% more capacity ? Theoreticaly yes, but actual consumption depends on the way you use your camera: how often you use zoom, prewiev, auto focus etc.

 

[cdiver2]

I am just looking into recharable batterys for my strobe and am unsure what mAh to get my question is what mAH is a Duracell AA so I can compare.

 

[MonkSeal]

cdiver2 once bubbled...
I am just looking into recharable batterys for my strobe and am unsure what mAh to get my question is what mAH is a Duracell AA so I can compare.

You can't compare rechargeable and non-rechargeable batteries:
- non-rechargeable last longer
- manufacturers don't give you the exact data
- capacity of non-rechargeable may vary

The device like strobe should work with rechargeable batteries without problems. The only important thing is that you synchronize changing batteries in strobe and in camera i.e. if batteries in camera last you two dives than same should apply for strobe.

 

[cdiver2]

I use a nikonos v so the camera battery problem is mute. I used to get four rolls of film from my strobe with Aks but it was slow to recharge on the last roll I have now gone to 1800 mah RC so I should expect 2 rolls maybe ?
Thanks for your help.

 

[Dee]

Monkseal is right....the bigger the mAh the better! As I've mentioned above, I've got 1500's as well as the 2200's and there's a big different in the length of time they last.

 

[sheck33]

size sure matters

buy the largest mAh capacity available.

these batteries are expensive so i would strongly suggest to buy a high quality charger for these batteries.

just an example: the D8 UK lightcannon is an expensive divelight with a rechargeable battery but it comes with a piece of crap charger that can potentially kill the battery or the charger itself in no time.

 

[TheAvatar]

More mAh means your toys run longer. More mAh is better.

Mostly, your choices will be between NiMH and NiCd batteries. I haven't seen many Li-ion or Li-polymer batteries except for cell phones and portable computers.

NiMH (Nickel Metal Hydride) have a higher power density (this makes them heavy for AA but gives them high capacity), last through more charge/discharge cycles (perhaps 500), and don't require the same level of care that NiCd batteries need and don't suffer from the memory effect as much. NiMH are expensive. Make sure you get the right voltage... many of these sometimes come as 1.2V in AA size. They should be 1.5V unless your manual states 1.2V is alright.

NiCd are old technology, but they recharge much faster than NiMH, they perform better at lower temperatures than either NiMH, Li-ion, alkaline nonrechargables, and Li nonrechargables. NiCds love high current applications. For example charging the cappacitor in your strobe: the NiCd will have your flash ready to fire again probably 30-40% faster than most other battery types except maybe Li, which it is about on par with. NiCd batteries tend to be very light weight because of their lower power density, which means while they recharge your strobe faster, they will give out sooner. Don't let their lower capacities (25-40% less than NiMH) scare you. NiCds recharge amazingly fast, but require care in how deeply and often they are discharged and recharged and require a charge discharge cycle once a month or they begin to suffer from memory effect (slow decreasing in capacity. NiCd are cheap cheap cheap. Make sure you get the right voltage... many of these sometimes come as 1.2V in AA size. They should be 1.5V unless your manual states 1.2V is alright.

Lithium nonrechargables: These are lighter than traditional alkaline nonrechargables. Amazingly, they also have a higher capacity despite their lighter weight (~25% more than alkaline, 50-100% more than NiMH, ~300% more than NiCd) and support high current applications and function better at low temperatures. For this reason, they are quite expensive. Make sure you get the right voltage... many of these sometimes come as 3.6V in AA size. You do NOT want to put 2 3.6V lithiums in a device expecting two 1.5V batteries.


For diving, I'd almost say NiCd is the way to go because they love high current apps like strobes and digicams. You are highly unlikely to exhaust a NiCd in one dive. They are cheaper than dirt so you can have a whole bunch. You can buy em on e-bay by the 2 dozen! Doing three dives? Have two sets of NiCds. It's probably cheaper than having one set of NiMH. Put new ones in after your first dive and recharge the used ones. They will be recharged by the time you come back from your second dive... unless it is a pretty short dive.

 

[Dee]

For more info on batter ies than you ever wanted to know...

Steve's Digi-Cam Battery/Charger reviews

The Great Battery Shootout

DP FWIW Batteries for Digitals

FYI....I use PowerX batteries. Currently 2200 mAh but I've got them from 1500 and up. My charger is a MAHA 204F, in fact I have 2 of them.