Why can't my electric stapler use Nicad batteries ?

[Rodo]

Hi all,

I just got an inexpensive ($15) electric stapler from Staples and the manual
says that it is ok to use alkaline batteries but not to use regular
manganese or nickel cadmium ones. Anyone know why ? will it hurt the nicads
if I do use them ?

Thanks

 

[Frank Bemelman]

Hi all,

I just got an inexpensive ($15) electric stapler from Staples and the manual
says that it is ok to use alkaline batteries but not to use regular
manganese or nickel cadmium ones. Anyone know why ? will it hurt the nicads
if I do use them ?

Not enough current and/or voltage. Nicads are 1.2 volt.
It won't hurt but probably don't stitch either.

 

[Clive Tobin]

"Rodo" <[email protected]> schreef in bericht
Not enough current and/or voltage. Nicads are 1.2 volt.
It won't hurt but probably don't stitch either.

But... alkaline cells spend most of their useful life around 1.2 - 1.25
volts also. They are 1.5 - 1.55 only when fresh. So I doubt if this is
the answer.

 

[John Woodgate]

I read in sci.electronics.design that Clive Tobin <[email protected]>
wrote (in <[email protected]>) about
'Why can't my electric stapler use Nicad batteries ?', on Sat, 1 Oct
2005:

But... alkaline cells spend most of their useful life around 1.2 - 1.25
volts also. They are 1.5 - 1.55 only when fresh. So I doubt if this is
the answer.

The other answer is that the low Ah capacity of cells, especially NiCds,
other than hot alkalines has generated complaints about the product
'eating batteries'.

 

[Jim Thompson]

But... alkaline cells spend most of their useful life around 1.2 - 1.25
volts also. They are 1.5 - 1.55 only when fresh. So I doubt if this is
the answer.

Probably has to do with surge current.

...Jim Thompson

 

[Kryten]

Nickel-based rechargables have a relatively high self-discharge rating.

Which is not what you want in something that sits doing nothing most of the
time, such as remote-control handsets or staplers.

Alkaline cells will typically last a year in an IR handset, whereas
NiCd/NiMH cells self-discharge way sooner.

Nickel cells are best suited for things that get through cells quickly, e.g.
power drills, Walkmans, MP3 players, etc.

 

[Ian Stirling]

Hi all,

I just got an inexpensive ($15) electric stapler from Staples and the manual
says that it is ok to use alkaline batteries but not to use regular
manganese or nickel cadmium ones. Anyone know why ? will it hurt the nicads
if I do use them ?

Thanks

I wonder about a very cheap mechanism, that relies on the stall torque
of the motor to not damage the mechanism.
Torque will be higher with NiCd at high loads.

 

[Phil Allison]

"Jamie"

Nicads don't like large loads on them.

** On the contrary - they thrive on heavy loads.




.......... Phil

 

[Phil Allison]

"Rodo"

I just got an inexpensive ($15) electric stapler from Staples and the
manual says that it is ok to use alkaline batteries but not to use regular
manganese or nickel cadmium ones. Anyone know why ? will it hurt the
nicads if I do use them ?

** The warning against Ni-Cds is most likely a safety issue.

An alkaline AA will deliver about 10 amps if shorted while a Ni-Cd AA can
deliver up to 50 amps - enough to burn wiring and destroy small motors.



......... Phil

 

[Engineer]

Nicads don't like large loads on them.
a stapler can produce large loads.
and also they are lower in voltage and dont last
as long .

Not so. The can deliver very high currents. That's why they are used
in drills and screwdrivers.
Cheers,
Roger

 

[Rodo]

This may make sense. The stapler has a small motor to do the stapling.

Thanks .. to everyone.

 

[Jamie]

But... alkaline cells spend most of their useful life around 1.2 - 1.25
volts also. They are 1.5 - 1.55 only when fresh. So I doubt if this is
the answer.

Nicads don't like large loads on them.
a stapler can produce large loads.
and also they are lower in voltage and dont last
as long .

 

[Jamie]

Not so. The can deliver very high currents. That's why they are used
in drills and screwdrivers.
Cheers,
Roger

i beg to differ, yes they are used in cordless screw drivers and such.
and when it comes to high currents!, i have seen nicads blow their
caps off from inrush of too many accurancies. the factor between
nicads and Alkaline is that they can be recharged and that is the main
reason whey they are used in such equipment. most devices that expect
inrush currents are designed not to put the nicad cells into a state of
super heating.
the fact remains that Alkaline provides higher voltages and actually
maintain a charge for longer periods.
and yes, a stapler can get Alkalines hot also when used in successions.
etc.
P.S.
i don't give much crecdence in Rechargeable Alkalines, i haven't found
any yet that can maintain the life cycle like a non rechargeable type.

 

[ehsjr]

i beg to differ,

Can you post some urls that support your position?
Ed


yes they are used in cordless screw drivers and such.

 

[Roger Hamlett]

I suspect it is though...

Can you post some urls that support your position?
Ed

There are several that will support this. Try:
http://www.technick.net/public/code/cp_dpage.php?aiocp_dp=guide_bpw2_c09_01
or:
http://www.powerstream.com/BatteryFAQ.html
Note particularly the comments uder the NiCd type.
Historically, this is why NiCd batteries ar still favoured, in 'traction'
type applications (together with lead acid). There are new generation NiMh
batteries that are starting to move into this market (look at cordless
drills, where some makes are now moving to NiMh), and these have
comparable or even slightly better maximum currents. There ae two 'parts'
to this, both the relatively low internal resistance (which is what
matters in the mobile phone application), and also relatively good
performance from the cell as it's temperature rises. This is why
lead-acid, or NiCd batteries are being used in current electric car
designs, and NiCd batteries for electric flight.
NiMh, give higher total power capacities, but it their high capacity
versions, have higher self-disharge rates.

As with all such things, there is a problem with 'generalisations'. High
capacity batteries, usually have less actual electrolyte, thinner
electrodes, and higher internal resistances. If one of these is
substituted into an application designed for a battery supporting high
currents, the result can very easily be cell rupture. Most manufacturers
do both types in a specific chemistry. NiCd cells designd for traction
use, are different 'beasties', from the sort commonly sold.

I suspect the real problem, is in cell voltage. The original poster,
refers to the battery as 1.5v nominal, and then points out that a
significant percentage of it's 'life', will be spent with a working
voltage comparable to the NiCd cell. The 1.5v nominal voltage and
discharge curve being talked about, sounds like that for a zinc-carbon
battery, not the alkaline cell. For medium loads, this maintains a voltage
over 1.25v much further into the design life, than for a zinc-carbon, or
NiCd cell. I suspect the stapler, is one of an unfortunately 'common'
class of devices, which only uses the first perhaps 40% to 50% of the
cells capacity, and requires the higher voltage available here, which is
not offered by the NiCd cell...

yes they are used in cordless screw drivers and such.

Best Wishes

 

[ehsjr]

I suspect it is though...



There are several that will support this.

Roger, I think you missed his point. He - the poster who said
"I beg to differ" stated earlier: "Nicads don't like large loads
on them. a stapler can produce large loads. and also they are
lower in voltage and dont last as long . " He differs with the
statement that nicds "can deliver very high currents. That's why
they are used in drills and screwdrivers. "

Ed


Try:

 

[Roger Hamlett]

Roger, I think you missed his point. He - the poster who said
"I beg to differ" stated earlier: "Nicads don't like large loads
on them. a stapler can produce large loads. and also they are
lower in voltage and dont last as long . " He differs with the
statement that nicds "can deliver very high currents. That's why
they are used in drills and screwdrivers. "

Ed

OK. I was 'differing' with the wrong person. However it is important
to realise that a high capacity NiCd battery, not built for high loads,
would then agree with the differer!. This is the big problem with such
generalisations....

Best Wishes

 

[Frithiof Andreas Jensen]

Hi all,

I just got an inexpensive ($15) electric stapler from Staples and the manual
says that it is ok to use alkaline batteries but not to use regular
manganese or nickel cadmium ones. Anyone know why ? will it hurt the nicads
if I do use them ?

What happened when you tried it??

 

[SioL]

What happened when you tried it??

Perhaps motor performance would suffer since nicads are only 1.2V and
regulars are 1.5V. Can't think of any other reason.

 

[Spehro Pefhany]

Perhaps motor performance would suffer since nicads are only 1.2V and
regulars are 1.5V. Can't think of any other reason.

The design may depend on the internal resistance of the cell(s) being
in a certain range. NiCds being lower in source impedance than
alkalines might fry the innards.

Before you laugh, there are plenty of LED flashlights that use the
battery resistance as the only series resistance outside of the LED
itself.


Best regards,
Spehro Pefhany