How to calculate the power of a battery.A battery that reaches 12V but is less than 20Ah may not be able to drive.
20Ah is the capacity of the battery, not the power. When the current is constant, the larger the capacity, the longer it can be used for power supply.
20Ah means that when the battery output current is 20A, it can be used for 1 hour, or it can be understood as when the battery output current is 2A, it can be used for 10 hours, etc. The product of current and time is 20Ah.
When the device requires a high-power battery of 20Ah to drive, it indicates that the operating current of the device is high, and small capacity batteries may not be able to withstand this high current.
The capacity of a battery, not its power, is the amount of time it can operate an appliance of a certain power. The length of the operating time depends on the power of the appliance.
In addition to 100Ah, the battery also needs to know the voltage level. This battery can operate for 1 hour at 100A current, and the specific power depends on the voltage of the battery. For example, a 12V battery can operate a 1200 W appliance for one hour with a current of 100A, and for 10 hours with a current of 10A. It depends on how much current is used to determine the working time.
The battery does not talk about power, but about "mAh", which means how long it can be discharged, is its battery capacity. The voltage of the new regular No. 5 dry battery is 1.5V, with an internal resistance of about 1 Ω, and the voltage will decrease during discharge. If the discharge current reaches 500 mA, a voltage drop of 0.5V will be generated, resulting in an output voltage of only 1V. The larger the discharge current, the smaller the total discharge capacity and the shorter the lifespan. The continuous discharge life is shorter.
From a unit perspective:
The unit of power is watts (W), denoted by P=UI and 1W=1VA (one watt equals one volt. ampere)
Battery capacity mA. h (milliampere hour), unit of electrical energy and work joules (J)
W=Pt
It is known that 1J=1W. s=1V A. S (one joule equals one volt ampere second)
In fact, the unit of measurement is essentially the same as that of electrical energy. To convert it:
1V.mA.h=1V*10^-3A*3600s=3.6V. A.s=3.6J
A battery is an energy storage component, and there is no such thing as power. It has a rated capacity, measured in Wh, which can be obtained by multiplying the voltage by the capacity.
For example, a "12V12Ah battery" does not mean that its power is 144W, which is 12 * 12!
12V12Ah battery "refers to the capacity of the battery. The rated working voltage of the battery is 12V. If the discharge current is 1A, it can be used for 12 hours; if the discharge current is 0.1A, it can be used for 120 hours; if the discharge current is 0.5A, it can be used for 24 hours;
Another indicator of a battery is its rated operating current. Generally, do not exceed the rated working current when using, as the battery has a longer lifespan. Otherwise, the lifespan will be shorter.
To connect a 300W lamp, the discharge current of the battery is required to be: I=P/U=300/12=25 A。 If it does not exceed the rated current of the battery. Can be used; If it exceeds, or even exceeds a lot, it cannot be used.
If it can be used The approximate usable time is 12Ah/25A=0.48h. Considering that the inverter itself, battery itself, and circuit have losses, it is shorter than 0.48h.
1. MAh "is the unit of battery capacity, and its Chinese name is milliampere hour (when measuring large capacity batteries such as lead-acid batteries, it is generally represented by" Ah "and its Chinese name is ampere hour).
1mAh=0.001A*3600s=3.6As=3.6C
2. Coulomb is a unit of electricity, not a basic unit of the International System of Units, but a special unit of the International System of Units. 1C=1A · s.
The amount of electricity transported within 1 second with a current of 1A, i.e. 1C=1A · s.
3. Formula for calculating electrical power: P=UI。 The unit of P is watts (W); In a pure resistance circuit, according to Ohm's law, U=IR can be substituted into P=UI to obtain: P=I*IR=(U*U)/R
Direct algorithm:
1. First, obtain the current of the electrical equipment.
2. The usable duration is obtained by dividing the battery capacity by the current of the electrical device.
