batteriescurrentpower supply
Can you draw 12mA from a CR2032 (or RL44) cell for long time? The data sheets says ~240mAH means about 24 hours to 2V, but it says that for draw less than 1mA typical…
And if there is no max, can I calculate the capacity — mAH, as a const, or does it change according to the current draw?
Does pulses draw is better or worse for capacity?
Is there a "home" (a place where you put that battery into such as other cells have)?
Cells in devices that you do not wish to be a flaming ruin MUST have protection.
Having protection circuits does not guarantee it will not happen.
Cells without protection are intended for use by either manufacturers or experts or enthusiasts who add their own or for suckers.
Whole device protection and cell protection are complementary and serve overlapping but different roles.
4,000 mAh 18650 LiIon batteries are ~~~= 99.9% +0.1% - 0.0% sure to be rubbish.
ie not just < 4000 mAh but << 4000 mAh and low quality.
The people who bogus label cells
almost never feel an obligation to use the best cells they can and
almost always decide to add injury to insult by using junk as well as lying.
Real world experience shows that the value of 'almost' is very high in both cases.
Higher capacity cells can usually be fitted OK.
MUCH higher capacity will lead to long CC tails and overcharge but not an issue here as mAh_new is < to << 4000 mAh.
Notice that in this ad and all their other ads they ALWAYS show non-brand-label views of the battery.
However, you may find that the racing stripes and general colour scheme a good match for the well known "Ultrafire" brand batteries. This may in fact be a real brand and these may be real examples of it BUT you can buy empty shrink wrappers to apply to the battery of your choice with this (or other) branding on it , so caveat emptor. Better nullius emptor I'd hazard.
These ones are a stunning 6800 mAh - a steal at the price. Available here
You'll find others similarly arrayed here and
here - 3000 mAh and 4000 mAh and
and unspecified but with GENUINE CREE 2000 lumen {so 20+ Watt} flashlight for $9.27 and
only 4000 mAh and
that's better - 4200 mAh
and .............
Flee!
2200mAh AA (14500) NiMH cells are available commonly, so 280mAh for a 1/3AA actually sounds a little low. I would expect 600mAh from that size instead.
Rather than putting multiple 1/V150Hs in series you might be better with one or more 4/V150Hs or 5/V150Hs on the same page. Putting them in parallel will let you easily hit your 2h life.
Best Answer
As a rule, higher current you draw, lower the capacity is. That is because when the call get discharged, the internal resistance becomes higher and the voltage drop as well.
Anyway, in general, the cell developers always try to increase this effect and to lower the internal impedance. But sometimes it is not easy task, together with the other parameters of the cell, for example the shelf life.
That is why there are many types of cells and you should choose the type you need for your application. The corresponding data sheet must contain a data about maximal allowed current and how the capacity is affected by the current.
Mentioned CR2032 is designed to provide small currents for low power electronic devices for very long time with very low selfdischarge. It means that probably you should not use it with very high currents. 20..30mA is the maximum on my estimation.