How is the battery capacity calculated according to the load power?

Battery capacity is usually expressed in terms of "A/H". Such as: 20A / H, 1 amp discharge can be maintained for 20 hours, discharge 2 amps can be maintained for 10 hours. Some are marked with the maximum discharge current, such as: 10A12V battery * 10A = 120W. As long as the electric appliance is not larger than this power, it can be driven.

The capacity of the battery is usually expressed in amps and hours (abbreviated as AH, 1A.h=36000C). The calculation formula of the battery capacity C is C=I∫t0tdt. The battery capacity is divided into actual capacity, theoretical capacity and rated according to different conditions capacity.

The minimum capacity to be discharged at a certain discharge rate at 25 ° C to the termination voltage is the capacity of the specified battery at the time of design and production. This is called the rated capacity of a certain discharge rate RH.

The battery capacity is generally calculated in AH (ampere-hours), and the other is calculated in CELL (unit plate) several watts (W). (W/CELL)

1. AH (ampere hour) calculation, defined as 20 hours. For example, a 7AH battery refers to a continuous discharge current of 0.35 A for 20 hours in a row.

2. W (W (power consumption) / CELL (unit plate)) calculation, the definition is based on 15 minutes. For example, 1221W battery is 12V (6CELL), each CELL power supply 21W can supply power for 15 minutes.

3. The charging time is based on 10 hours, and the charging current is 1/10 of the battery capacity. Fast charging will reduce battery life. Battery capacity refers to the amount of battery storage. The unit of battery capacity is “MAH”, and the Chinese name is MAH (when measuring large-capacity batteries such as lead storage batteries, for the sake of convenience, it is generally indicated by “Ah”, the Chinese name is Anshi, 1Ah=1000mAh). If the rated capacity of the battery is 1300mAh, if the battery is discharged with 0.1C (C is the battery capacity), that is, 130mA, then the battery can work for 10 hours (1300mAh/130mA=10h); if the discharge current is 1300mA, then the power supply The time is only about 1 hour (the actual working time varies depending on the individual differences in the actual capacity of the battery). This is an analysis under ideal conditions. The current of a digital device in actual operation cannot always be constant at a certain value. (In the case of a digital camera, the operating current will be large due to the opening or closing of components such as the LCD display and flash. Change), so the battery can only provide a certain value for the power supply time of a device, and this value can only be estimated through practical experience.

Regulator technical parameters

A, the regulator has an input voltage adaptation range. The IEC standard changes the input voltage within ±10% of the rated value. The input range of our products is ±15%. The out-of-range automatic sound and light alarm cannot stabilize the output voltage within the required range.

B, the output voltage regulation rate is the effect of the change of the input voltage caused by the change of the input voltage. When the load is rated, the input voltage is adjusted upward from the rated value to the upper limit value and the lower limit value according to the source voltage range, and the measurement is performed. The maximum amount of change in output voltage (±%). The smaller the value is, the better, which is an important indicator of the performance of the AC voltage regulator.

C, load adjustment rate: is the effect of changes in output caused by changes in output. Change the load current and measure the amount of change in the output voltage (±%). The smaller is the value, the better. It is also an important index to measure the performance of ac voltage stabilizer.

D, the relative harmonic content of the output voltage (also known as the output voltage distortion), usually expressed by THD, is the ratio of the total effective value of the harmonic content to the effective value of the fundamental wave. When the load is rated, the input voltage distortion satisfies the reference. When the condition (generally less than 3%), measure the output voltage distortion when the input voltage is the lowest value, the rated value and the highest value, whichever is the largest. The smaller is the value, the better.

E, efficiency: is the ratio (percentage) of the output active power P0 to the input active power Pi,

F, load power factor

The regulator capacity is expressed in terms of volt-amperes (VA) or KVA. In addition to the purely resistive load, there are inductive and capacitive loads in the load, that is, in addition to the active power in the load, there is no Power. This pointer reflects the ability of the AC regulated power supply with inductive and capacitive loads.

Generally, the AC regulated power supply has a load power factor of cosφ of 0.8. When the product is 1KVA, the output active power (ie, the capacity of the resistive load) is up to 800 W. If the product is expressed in 1 kW (cosφ is still 0.8), the output active power is 1KW, and the power that can be output is S=1000/0.8=1250VA. When the value of the load power factor is small, it indicates that the power supply device has a strong ability to adapt to the reactive load.

G, AC voltage regulator parameters are also output power, input frequency, source frequency effect, random deviation (time drift), no-load input power, source power factor (this value is different from load power factor, hopefully the bigger the better, the largest It is 1), source current relative harmonic content, audio noise, etc., three-phase AC regulated power supply, and three-phase output voltage unbalance. The definition and test methods of these pointers can refer to relevant standards.

The amount of electricity discharged by the battery under specified conditions (including discharge intensity, discharge current and discharge termination voltage) or the length of discharge time is called battery capacity, and the unit is A·h or A·min. A car battery is a reversible DC power source that converts chemical energy into electrical energy and electrical energy into chemical energy. It is connected in parallel with the generator.

It supplies power to the starting system and the ignition system during engine start.

When the engine is stopped or low idle it supplies power to the car's electrical equipment.

When there is a demand for electricity exceeding the output of the charging system, the current is supplied by this for a limited period of time.

The battery also absorbs the transient overvoltage in the circuit to keep the voltage of the automotive electrical system stable and protect the electronic components.

The battery will not be used for a long time, it will slowly discharge itself until it is scrapped. Therefore, the car should be started once every certain time to charge the battery. Another method is to pull out the two electrodes on the battery. It is necessary to remove the positive and negative electrode wires from the electrode column. First, unplug the negative wire or remove the connection between the negative electrode and the chassis of the car. Then remove the other end with the positive mark (+). The battery has a certain service life and will be replaced in a certain period of time. The same order should be followed when replacing, but when the electrode wires are connected, the order is reversed, first connected to the positive electrode and then to the negative electrode.

When the ammeter pointer indicates that the storage capacity is insufficient, it should be charged in time. The battery's storage capacity can be reflected on the dashboard. Sometimes the power is not enough on the road, and the engine can't start. As a temporary measure, you can ask other vehicles for help. Use the battery on the vehicle to start the vehicle, connect the negative and negative poles of the two batteries, and connect the positive pole to the positive pole. .

The density of the electrolyte should be adjusted according to the standard according to different regions and seasons.

Distilled water or special rehydration solution and nano-carbon sol battery activator should be added when the electrolyte is deficient. Never use pure water instead. Because pure water contains a variety of trace elements, it will have an adverse effect on the battery.

Uninterrupted use of the starting opportunity when starting the car causes the battery to be damaged due to excessive discharge. The correct method of use is to take no more than 5 seconds for each time the car is started, and the interval between starts again is not less than 15 seconds. In the case of multiple starts and still not in the car, you should find the reason from other aspects such as circuit, ignition coil or oil circuit.

Always check the small holes in the battery cover for ventilation when driving daily. If the small hole of the battery cover is blocked, the generated hydrogen and oxygen will not be discharged, and when the electrolyte expands, the battery case will be broken and the battery life will be affected.

Check the positive and negative levels of the battery for signs of oxidation. You can use hot water to constantly pour the wire connection of the battery.

Check the presence or absence of aging or short-circuiting in all parts of the circuit to prevent the battery from being decommissioned early due to excessive discharge.

1. over discharge

2. The battery is stored for a long time (not charged during storage)

3. Cannot be charged by car engine

4. No electrolyte

5. The electrolyte is too high

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