1. Electricity Q = IΔt = (P/U) · t = (130W/14.8V) · 3600s = 31621 C (Coulomb)
Time: t = W/P = 130Wh/28W = 4.64h
2. Current = 6400mA? Mah.
Q = IΔt = 6.4A·1h = 23040 C
t = W/P = UI/P = 7.4V·6400mAh/18W = 2.63h
>Explanation:
Battery energy E = UIt, mAh is the unit of charge, Wh is the unit of energy
t = E/P
Detailed information:
Lithium metal battery:
Lithium metal battery generally uses manganese dioxide as the positive electrode material, lithium metal or its metal alloy as the negative electrode material, and uses a non-aqueous electrolyte solution. .
Discharge reaction: Li+MnO2=LiMnO2
Lithium-ion battery:
Lithium-ion batteries generally use metal oxide alloy lithium as materialcathode water and graphite. as cathode material. Negative electrode materials, batteries using non-aqueous electrolytes.
The reaction that occurs on the positive charge electrode is
LiCoO2==Li(1-x)CoO2+XLi++Xe-(electrons)
On the negative charge electrode The reaction that occurs is
6C+XLi++Xe-?= LixC6
The total reaction of the rechargeable battery: LiCoO2+ 6C = Li( 1-x)CoO2+LixC6
Positive electrode
Cathode material: There are many optional positive electrode materials, and most common products use lithium iron phosphate.
Positive reaction: lithium ions are intercalated during discharge and lithium ions are deintercalated during charging. When charging: LiFePO4?→ Li1-xFePO4?+ xLi+ + xe- When discharging: Li1-xFePO4?+ xLi+ + xe-?→ LiFePO4.
Anode
Anode material: Graphite is mainly used. New research revealst that titanate might be a better material.
Anodic reaction: lithium ions are disintercalated during discharge and lithium ions are integrated during charging.
When charging: xLi+ + xe-?+ 6C → LixC6
When discharging: LixC6?→ xLi+ + xe-?+ 6C
< p> References:
1. The most direct algorithm:
First get the current of the electrical appliance, then divide the battery capacity by the current of the electrical appliance. The result is the duration of use.
For example:
A 3000mAH battery with a rated voltage of 5V powers an electrical appliance with a power consumption of 2.5W and a voltage of 5V. Its theoretical useful life is . :
I=P/U => 2.5w/5v => 0.5A => 500MA.
3000mAh means that a current of 3000MA can be discharged for one hour,
3000/500=6 hours.
2. Coulomb charge algorithm:
C=IS => 3A*3600s => 10800c Coulomb (charge).
Electric energy 10800c*5v=54000w.
54000w/2.5w=21600/3600s=6h.
Detailed information
Common batteries
1 Dry batteries
Dry batteries are also called manganese- . Zinc batteries, called dry cells, are compared to voltaic batteries, and the term manganese-zinc refers to their raw materials. For dry cell batteries made from other materials such as silver oxide batteries and nickel cadmium batteries. The manganese-zinc battery voltage is 1.5V. Dry batteries consume chemical raw materials to generate electrical energy. Its voltage is not high and the direct current it can produce cannot exceed 1 ampere.
2. Lead acid battery
The battery is one of the most used batteries. Use a glass tankor plastic, fill it with sulfuric acid and insert two lead plates, one is connected to the positive electrode of the charger and the other is connected to the negative electrode of the charger. , a battery is formed. There are 2 volts between its positive and negative terminals. The advantage of batteries is that they can be used repeatedly. In addition, its internal resistance being extremely low, it can provide a significant current. Use it to power the car engine, and the instantaneous current can reach more than 20 amps. The battery stores electrical energy when charging and converts chemical energy into electrical energy when discharging.
3. Lithium battery
The advantages of lithium battery are high single cell voltage, high specific energy, long storage time (up to 10 years), good high and low performance temperature, and can be used at -40~150℃. The disadvantagesnts are that it is expensive and unsafe. Additionally, voltage mismatch and safety issues need to be improved. The vigorous development of power batteries and the emergence of new cathode materials, especially the development of lithium-iron-phosphate materials, are of great help to the development of lithium batteries.