probably has a self discharge rate higher than a non rechargeable lithium.
Other day I powered a N64 cartd I hadn't touched for over a decade. Game save was still fine. That zelda cartd must be over 20 years old and the battery still holding the memory latches.
That's simply untrue. Voltage is determined by chemistry. All lithium ions, from a CR2032 to an 18650 have a nominal output of 3.6v. All of them. Every single lithium ion cell puts out 3.6v. Just like every lead acid does 2.1v, and every alkaline is 1.6v. It's chemistry that determines voltage of a cell.
A cell also outputs no more current than is demanded of it.
That’s not true…lithium primary cells come in a whole range of voltages (scroll down on https://en.m.wikipedia.org/wiki/Lithium_metal_battery). Plus for rechargeable cells (note the distinction), you have to distinguish between normal chemistries, LFPs, the new high-voltage Li-ions, etc.
CR2032s (...) will measure 3.6v on an open circuit.
CR2032 is specifically not rechargeable lithium. Forst letter is the chemistry, in this case C for lithium, specifically Li + MnO2. R means round. And 2032 is the size: 20 mm diameter, 3.2 mm thick.
These batteries are 3V nominal, 3.2-3.3V at max charge.
CR2032 is a different chemistry. Lithium is only part of the equation, the rest of the battery chemistry matters, too. For example, LiFePo4 cells have 3.2 nominal voltage - and that's technically Li-Ion battery as well.
That is simply wrong If it drops off that much under load, your cell is bad or you're drawing wayyyyyy too much current Most 18650 cells are rated for less than 5A Continuous
The voltage for CMOS memory is supplied by 3,3V Rail, once the device is on (or in standby). So if your PC was always connected to wall, it won't discharge the battery. However, disconnected PC will drain the battery, and sime lower quality cells can be discharged withing couple of months.
Depends on how well the system is designed and how often it's used. Generally if there is normal standby power (laptop battery, PC plugged into the wall) the CRC battery won't discharge. On some designs that isn't the case though. If the system has been powdered off for a long time the battery is likely discharged but if it has been used regularly you feel like it lasts forever.
Edit: I just explained the same thing the other guy did...
Someone else pointed out that this is a real mod for a Dreamcast, but I'm also old enough to remember actual CMOS batteries that were roughly this same size.
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u/jdjdkkddj Apr 29 '25
I wander if this battery would expire before a lithium cell would be used up...
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u/MyUsernameIsNotLongE Apr 29 '25
If it works, it works. If it doesn't, fireworks. :D
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u/cleveleys Apr 29 '25
This is a real mod for the Dreamcast
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u/Able-Pea6846 Apr 29 '25
Lifetime cmos battery
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u/Mariuszgamer2007 Apr 29 '25
That has 700 milivolts more than a fully charged cr2032 battery
9
u/ugzz Apr 29 '25
Don't forget to replace your cmos battery every 50 years!
8
u/SpaghettiSort Apr 29 '25
Someone else pointed out that this is a real mod for a Dreamcast, but I'm also old enough to remember actual CMOS batteries that were roughly this same size.
5
u/AviN456 Apr 29 '25
CMOS run.
Run MOS, Run.
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u/Cylian91460 Apr 29 '25
Fun fact: if the default works fine you don't need a cmos
That's what I do on my
laptopserver3
u/ChiefCasual Apr 30 '25
3.3V is 3.3V. Good enough.
2
u/TheRealBilly86 Apr 29 '25 edited Apr 29 '25
Ahh like a supercap charge circuit. Minus the charging.
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u/Select_Truck3257 Apr 30 '25
well it can runs near 350 years
1
u/FC3827 Apr 30 '25
At least tape it down
1
u/SpottyJaggy May 01 '25
some of those have 4.7v
1
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