Are Alkaline batteries usually better for low load applications?

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Zebretta
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Are Alkaline batteries usually better for low load applications?

Tried some good rechargable AAA’s in some low drain devices and TBH, the Alkalines last a LOT longer.
About 2 weeks for the Alkys and about 4 days for the rechargeables.

Probably because the cut-off voltage for the devices is around 1.34v

Are there any rechargable AAA’s that are good for low drain applications?

Lexel
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At 1.34V cutoff voltage the NiMh batteries are more than 85% full

For your device NiZn rechargable batteries with 1.6V may work, but the device needs to survive the voltage of a fresh fully charged cell

http://www.akkushop.de/de/ansmann-nickel-zink-lr03-aaa-nizn-akku-16-volt...

joechina
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Normally yes, I have a digital clock 20 years old and changed the AAA twice.

You could try NiMH made for wireless phones they have normally a higher inner resistance.

I wonder if a batteriser (they are normally BS) could do the trick, because your device has this high cut off voltage.
https://en.m.wikipedia.org/wiki/Batteroo_Boost

Please correct me if I’m wrong.

wle
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LSD NiMh is better but they age, and even when new, they still self discharge.
The LSD means “low self discharge”.
Also advertised as ‘pre-charged’.
Eneloops were the first, others followed.

Alkalines are best where either the load is very low [clocks], or the device is basically never used but you want it ready [flashlight by the furnace under the house].

Pete7874
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joechina wrote:
You could try NiMH made for wireless phones they have normally a higher inner resistance.

Why would higher IR be a good thing?
Zebretta
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Lexel wrote:
At 1.34V cutoff voltage the NiMh batteries are more than 85% full

For your device NiZn rechargable batteries with 1.6V may work, but the device needs to survive the voltage of a fresh fully charged cell

http://www.akkushop.de/de/ansmann-nickel-zink-lr03-aaa-nizn-akku-16-volt...

I see where HKJ did a review of these batteries and his conclusion?
NiZn Review by HKJ

_“The cells might be useful for some special applications, but as replacement for alkaline or NiMH they are not very good. The higher voltage might damage equipment and the cells will be damaged when discharged to much.
I do not believe the cells are useable as replacement for alkaline or NiMH_.”
.
.
On the other hand……
If the device I want to use it in has an internal voltage cut off of 1.34v then I would never have to worry about over discharging right?

joechina
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A high IR limits the self discharge.

So when you draw very little current, like in clocks, the current over a low IR can be significant to reduce runtime.

He said it’s low drain and with the high cut out = bad runtime.

Newer good designed devices should work with 0.8V to 1V, than you can use all the energy from a NiMH and alkaline.

flydiver
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joechina wrote:
A high IR limits the self discharge.

Are you sure? In my experience high IR indicates an old and failing battery that have much worse self discharge.
Good batteries like Eneloop always have a low IR, at least when new and good.
High IR will limit the current output, that’s for sure. They can only be low load.

Zebretta
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I ordered a few NiZN batteries to “try”, since the device I want to use them in does have the 1.34v cutoff so that means the NiZn’s won’t be damaged by over discharging (which I hear is their biggest killer). I was planning to only charge them to 1.7v thinking that that would “probably” not harm the device. Of course, that means they will not be fully charged.

I’m just looking for a balance. AAA Alkalines last about 18-25 days in the device (depending on the quality of the alkaline). If I can get the NiZn’s to power the device for 15 days I would be satisfied.

It’s also not “mission critical” by an means. I’m mainly having fun experimenting with the different chemistries. If I end up throwing out 4 useless NiZn batteries and just using Alkalines in the device that’s ok too.

Boaz
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you say you tried some “good “ nimh’s // What make what model ? and in what kind device ?

καὶ τὸ φῶς ἐν τῇ σκοτίᾳ φαίνει καὶ ἡ σκοτία αὐτὸ οὐ κατέλαβεν