hi guys, if a cell phone battery with 957mAh and 3.7V.
957mAh is the battery capacity, isnt it?
So, is it mean that the power require to fully charge the battery is (957 X 3.7)/1000000 = 0.0035 kWh ? (assume the battery is completely empty)
If it is true (need 0.0035kWh power to charge), is that also mean this is the power needed with regardless of the charging time? for example, 2 same capacity batteries may need different time to fully charge the battery, but the power it require is the same, is it truth? Because I am not sure the relationship between charging and the capacity.
Thank you very much!
2007-09-25 03:00:02 · 4 answers · asked by marco824xu 1 in Science & Mathematics ➔ Physics
The nominal battery voltage is 3.7V, determined only by the battery chemistry (probably nickel metal hydride) and number of cells. The 957mAh is the capacity in milliampere-hours. That means it could provide the equivalent of almost 1 ampere for one hour. They are usually rated at "0.1C", so you could reasonably expect to draw one tenth of that (95.7mA) for 10 hours.
Charging is not 100% efficient, so charging at 0.1C would probably take 12-16 hours. That charge and discharge rate are appropriate for maximizing battery life.
Within the limits of the capability of the battery, you can choose whether to charge at a higher power for a shorter time, or a lower power for a longer time.
2007-09-25 13:24:15 · answer #1 · answered by Frank N 7 · 0⤊ 0⤋
mAh is milli-Amp/hour. So the battery can supply 957 milliAmps/hour of current. You can't determine it's capacity from this because who knows how long it will take to go dead. It could supply 957mAh for 4 hours or for 24 hours.
Also, the rate at which a battery can supply energy isn't necessarily the same rate at which it can charge.
2007-09-25 03:04:53 · answer #2 · answered by Anonymous · 0⤊ 1⤋
The charging time is never perfect, and the power draw for each type of battery is graphed.
A battery has a voltage rating, but also a tolerance, for example a 12V car battery varies between about 10 volts to 14 volts. similiarly your 3.7 volt battery might range from 3.2 to 4.1 volts. The charger voltage has to be at about 4.0 volts to charge it.
Most battery manufacturers have a graph of voltages and charge times.
2007-09-25 03:09:32 · answer #3 · answered by Feeling Mutual 7 · 0⤊ 1⤋
you could flip your telephone off to save extra battery... thats what i do whilst im on the bypass and dont have my charger for sure i pass over calls like that yet...my acquaintances can bypass away a message after the beep LOL
2017-01-02 15:59:45 · answer #4 · answered by Anonymous · 0⤊ 0⤋