12V15Ah LiFePO4 Battery
MAIN KIT INCLUDES
1 x 12V15Ah LiFePO4 Battery Module;
Battery Cycle Life
2000 Times @100%DOD 6000 Times @80%DOD
LiFePO4 18650 3.2V 1500mAh-4S10P
Reference Battery Size
Reference Battery Weight
Normal Charge Current
Normal Discharge Current
Max. Continuous Output Current
Max. Continuous Output Power
Passive Protection Function
Over charge protection; Over discharge protection; Over current protection, etc
Operation Temperature Range
Battery Storage Temperature
Individual Cell Approval
CE / RoHS / UN38.3 / UL 1642 / IEC 62133 / CB / KC / BIS
The product test data curve
Lithium-ion battery characteristics
Lithium is the smallest and most active metal on the chemical periodic table. The small size and high capacity density are widely welcomed by consumers and engineers. However, the chemical properties are too active and pose a very high risk. When exposed to air, lithium metal can explode with intense oxidation of oxygen. In order to improve safety and voltage, scientists have invented materials such as graphite and lithium cobalt oxide to store lithium atoms. The molecular structure of these materials forms a nano-scale fine storage lattice that can be used to store lithium atoms. In this way, even if the battery casing is broken and oxygen enters, the oxygen molecules are too large to enter these fine cells, so that the lithium atoms do not come into contact with oxygen to avoid explosion. This principle of lithium-ion batteries allows people to achieve high-density density while achieving safety.
When a lithium ion battery is charged, the lithium atom of the positive electrode loses electrons and oxidizes to lithium ions. Lithium ions swim through the electrolyte to the negative electrode, enter the cell of the negative electrode, and obtain an electron, which is reduced to a lithium atom. When discharging, the entire program is reversed. In order to prevent the battery from being short-circuited by direct contact between the positive and negative terminals, a separator paper with a large number of fine holes is added to the battery to prevent short circuit. Good diaphragm paper can also automatically close the pores when the battery temperature is too high, so that lithium ions can not pass through, so as to prevent the danger from happening.
When the lithium battery cell is overcharged to a voltage higher than 4.2V, it will start to have side effects. The higher the overcharge voltage, the higher the risk. When the lithium battery voltage is higher than 4.2V, the amount of lithium atoms remaining in the positive electrode material is less than half. At this time, the storage cell often collapses, causing a permanent drop in battery capacity. If the charging continues, since the cell of the negative electrode is already filled with lithium atoms, the subsequent lithium metal will accumulate on the surface of the negative electrode material. These lithium atoms grow dendrites from the surface of the negative electrode toward the direction of lithium ions. These lithium metal crystals pass through the separator paper, shorting the positive and negative electrodes. Sometimes the battery explodes before the short circuit occurs. This is because during the overcharging process, the electrolyte and other materials will crack and generate gas, causing the battery casing or pressure valve to bulge and rupture, allowing oxygen to enter and react with the lithium atoms deposited on the surface of the negative electrode. Then exploded. Therefore, when charging a lithium battery, you must set the upper voltage limit to take into account the battery life, capacity, and safety. The optimal charging voltage is limited to 4.2V.
The lithium battery has a lower voltage limit when it is discharged. When the cell voltage is lower than 2.4V, some materials will start to be destroyed. Since the battery will self-discharge, the voltage will be lower for a longer time. Therefore, it is best not to put it at 2.4V to stop. During the period from the discharge of 3.0V to 2.4V, the energy released by the lithium battery is only about 3% of the battery capacity. Therefore, 3.0V is an ideal discharge cutoff voltage.
In charge and discharge, in addition to the voltage limit, current limitation is also necessary. When the current is too large, lithium ions cannot enter the cell and will accumulate on the surface of the material. When these lithium ions obtain electrons, crystals of lithium atoms are generated on the surface of the material, which is dangerous as overcharge. In the event of a broken battery case, it will explode.
Therefore, the protection of the lithium ion battery must include at least three factors: the upper limit of the charging voltage, the lower limit of the discharging voltage, and the upper limit of the current. In the general lithium battery pack, in addition to the lithium battery core, there will be a protective board, which is mainly to provide these three protections. However, these three protections of the protection board are obviously not enough, and the global lithium battery explosion is still frequent. To ensure the safety of the battery system, a more careful analysis of the cause of the battery explosion must be performed. Lithium-ion battery characteristics