Apple Magic Mouse 1 Doesn't like NiMh batteries. Why?

[Jurek]

As above.
I have some rechargeable Vapex 2900mAh AAs showing > 1.4v on the meter, which won't run the mouse, and yet a pair of Duracells showing >1.4v will happily run it.
Any ideas as to why?

[grams]

As above.
I have some rechargeable Vapex 2900mAh AAs showing > 1.4v on the meter, which won't run the mouse, and yet a pair of Duracells showing >1.4v will happily run it.
Any ideas as to why?

Open circuit voltage isn't the same as what you get when you apply a load. I suspect you're getting a much lower voltage when the mouse tries to light up.

(although they are meant to be NiMH compatible - Apple even offered their own at point)

No but I will stand in line with Jurek: we have some battery powered Christmas lights which run on two AA batteries. Alkaline work fine but not a glimmer from NiMH. Why not?

Modern LEDs need very close to 3 volts to light up, and don't light up at all at lower voltages. 3 volts is what you get from a pair of alkalines, so cheapo lights have no drive circuitry at all (not even a dropper resistor) between the batteries and the LEDs.

NiMHs only get near that when they're fully charged, and quickly drop away under load, so might not be enough to spark them into life.

[Jurek]

Apropos of nothing in particular, I've just been on the phone to Technoline to order some replacement NiMH batteries (my Vapex fleet is ~ 15 years old).
Mr. Technoline didn't have a clue as to why the apparently charged Vapex wouldn't work in the mouse.

[ian]

My older two Magic Mice use bog-standard Maplins 2000 and 2500 mAh NiMHs without issue. While I fundamentally don't believe in electrickery, I presume it is some voltage-load related thing.

However, these same batteries won't operate the microchip cat flap, which demands fresh alkalines every several months.

[simonp]

15 year old batteries are much less likely to maintain voltage under load, IMO.

[fuaran]

Try some low self-discharge NiMH batteries. They are often more reliable than the regular type. And should last longer in something like a mouse.

[Greenbank]

I've just gone through my 40 odd rechargable batteries with my new Ansmann Powerline 5 Pro charger. Most of the batteries were 15 years old.

Of the 15 AAA batteries the charger only recognised 2 of them and it only manged to get ~300mAh into those two (they were Energiser branded and rated at 800mAh originally). Of the rest the majority just made the charger read "hI" (to signify too high a resistance when charging), and some would do the same after a few of the discharge/charge cycles on the charger's "refresh" program, some came out as "lo" to signify a different problem. I tried a few times, even forcing some charge into them with a couple of hours in a dumb charger, all to no avail.

The remaining AA batteries fared much better, although I think all of the 2700mAh Ansmann branded batteries I had are duds. Again the Energiser branded ones came out best, one even managed to take in a full 2.7Ah (the charger does not know the capacity of the battery it is dealing with, it just reports how much it thinks it managed to shove back in) but most were 1500mAh to 1900mAh.

So that's a whole bunch of rechargeables that are going in the battery bin at the local supermarket. I hope someone doesn't try and salvage them thinking they've been disposed of in error.

[Jurek]

15 year old batteries are much less likely to maintain voltage under load, IMO.

Yup! I think that through all the FNRTTCs I've ridden - I've probably had more than my mileage-worth from those Vapex.

Try some low self-discharge NiMH batteries. They are often more reliable than the regular type. And should last longer in something like a mouse.

The replacement Fujitsus that I've ordered are low self-discharge.
Although £75.00 for batteries!   

X-post with Greenbank.
Yes, a trip to supermarket with a bag full of past-their-best batteries.

..... I hope someone doesn't try and salvage them thinking they've been disposed of in error.

You could always give one end of the battery a squeeze inna vice, so that it is no longer cylindrical and doesn't fit chargers/appliances.

[ian]

My cheap Maplin ones are quite old (obviously) but keep the mouse happy for a couple of months at a time. The 2000 mAh ones are best, they must self-discharge slower.

This is with a Technoline charger, the bog-standard NiMH charger I used to use wouldn't get two weeks out of them.

[simonp]

I've just gone through my 40 odd rechargable batteries with my new Ansmann Powerline 5 Pro charger. Most of the batteries were 15 years old.

Of the 15 AAA batteries the charger only recognised 2 of them and it only manged to get ~300mAh into those two (they were Energiser branded and rated at 800mAh originally). Of the rest the majority just made the charger read "hI" (to signify too high a resistance when charging), and some would do the same after a few of the discharge/charge cycles on the charger's "refresh" program, some came out as "lo" to signify a different problem. I tried a few times, even forcing some charge into them with a couple of hours in a dumb charger, all to no avail.

The remaining AA batteries fared much better, although I think all of the 2700mAh Ansmann branded batteries I had are duds. Again the Energiser branded ones came out best, one even managed to take in a full 2.7Ah (the charger does not know the capacity of the battery it is dealing with, it just reports how much it thinks it managed to shove back in) but most were 1500mAh to 1900mAh.

So that's a whole bunch of rechargeables that are going in the battery bin at the local supermarket. I hope someone doesn't try and salvage them thinking they've been disposed of in error.

Batteries that aren't recognised are typically below 0.7V. They can often be resurrected by a charged battery (or a dumb charger). The trick with the charged battery is to connect them in parallel (piece of foil on a worktop, stand the batteries side by side with the -ve terminals on the foil, and then place another piece of foil over the +ve contacts). The charged battery acts like a charger and you can get enough in over a few seconds that it will then briefly register sufficient voltage to wake up a smart charger, if you transfer straight to the charger.

[Jurek]

My cheap Maplin ones are quite old (obviously) but keep the mouse happy for a couple of months at a time. The 2000 mAh ones are best, they must self-discharge slower.

This is with a Technoline charger, the bog-standard NiMH charger I used to use wouldn't get two weeks out of them.

According to Mr Technoline, 10 years on, his BL700 is still a best seller.
Given that both of mine are that sort of vintage, and that they are *on* all the time, they're not doing too badly.

Incidentally, if anyone likes to talk batteries, feel at liberty to give Mr Technoline a call.
He freely admits to talking batteries with a passion and, thanks to online shopping, bemoans the fact that that particular delight is largely missing from his world. I don't get the impression that he is picky about battery type.

Batteries that aren't recognised are typically below 0.7V. They can often be resurrected by a charged battery (or a dumb charger). The trick with the charged battery is to connect them in parallel (piece of foil on a worktop, stand the batteries side by side with the -ve terminals on the foil, and then place another piece of foil over the +ve contacts). The charged battery acts like a charger and you can get enough in over a few seconds that it will then briefly register sufficient voltage to wake up a smart charger, if you transfer straight to the charger.

According to Mr Technoline, the difference between the BL700 and the newer BL700n, is that the newer model will recognise batteries which have been run properly flat, and attempt to recharge them.

[ian]

I've found if my Technoline comes up with a null for a battery, then as suggested, a quick blast in old dumbo charger usually fixes it.

[Kim]

It's a trade-off, the higher capacity ones will self-discharge at a fair rate, but that doesn't matter if they're powering something that's going to drain them in a day or two (front lights, GPS receivers, that sort of thing), where the extra capacity is more important.  The low-self-discharge ones are better for things like rear lights, meece, remote controls, etc.

More and more of the applications that would have benefited from the higher-capacity cells have switched to lithium-ion rechargables.

[ian]

I put lithium-ion rechargeables in the security cameras, they're not bad, the charger is dumb so it can be hit and miss whether they last for a month or six. That said, the last time I tried to buy some spares, they were unobtainium.

[tonycollinet]

The "soft" coating on my 2014 vintage* BL700 has gone sticky and has a nice fury coat of carpet fluff.

Still works fine - though I am now tempted by the newer one that will have a go at discharged batteries.



_{*one of the nice things about gmail is the ability to instantly search decades of old emails and find stuff like this. In fact I don't use gmail for email, but still import all my incoming emails just for the search functionality.}

[Kim]

The "soft" coating on my 2014 vintage* BL700 has gone sticky and has a nice fury coat of carpet fluff.

You'd think manufacturers of stuff would have learned this lesson by now.  To the point where I'm suspicious that they're doing it deliberately, so that people replace an otherwise reliable product simply because it's gone sticky or is shedding high-grip coating.

My Logitech lefty mouse started shedding coating some years ago.  I put a film on, unplugged it and sat there scraping the coating off with a thumbnail/well-worn screwdriver.  By the end I had a perfectly usable bald mouse, and a lap full of black crumbs.  Still going strong, though I think I replaced a microswitch at one point.

one of the nice things about gmail is the ability to instantly search decades of old emails and find stuff like this

To be fair, even Thunderbollocks's search facility works fine for that, though you might have to wait a little longer for the results.  It's occasionally very useful.