To safely utilize lithium-ion or lithium polymer batteries, they must be paired with protection circuitry capable of keeping them within their specified operating range. The most important faults that the batteries mus. Lithium-ion (Li-ion) and lithium polymer (LiPo) batteries have very similar electrical characteristics but differ in packaging. Li-ion batteries are made with a rigid (typically cylindrical) casin. If the voltage across a Li-ion/LiPo cell is allowed to fall below its minimum operating value (typically around 2.5V or 3.2V depending on the exact cell), the cell willbe damaged. To wh. The regulated output of the BQ296xxx can be used to easily integrate other battery protection devices that have an active-low fault detection signal. As an example, consider the INA. Whether using Li-ion or LiPo cells, a battery management system is required to ensure that they are used safely and not worn out prematurely. Because undervoltage is not the most critical f.
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Why is undervoltage protection important for lithium ion batteries?
To safely operate such a battery, the discharge current rate and battery voltage level must be monitored. Undervoltage protection is crucial when using lithium-ion batteries because if the battery is discharged below its rated value, the battery will become damaged and potentially pose a safety hazard.
Do lithium-ion batteries need protection circuits?
However, the need for protection circuits to maintain the voltage and current within safe limits is one of the primary limitations of the lithium-ion battery.
Figure 1 shows an ultralow power, precision undervoltage-lockout circuit. The circuit monitors the voltage of a Li-Ion battery and disconnects the load to protect the battery from deep discharge when the battery voltage drops below the lockout threshold.
It contains both primary and secondary protections to ensure safe use of the battery pack. The primary protection protects the battery pack against all unusual situations, including: cell overvoltage, cell undervoltage, overtemperature, overcurrent in charge and discharge, and short-circuit discharge.
Further layers of safeguards can include solid-state switches in a circuit that is attached to the battery pack to measure current and voltage and disconnect the circuit if the values are too high. Protection circuits for Li-ion packs are mandatory. (See BU-304b: Making Lithium-ion Safe)
Are lithium batteries safe?
Lithium batteries have the advantage of high energy density. However, they require careful handling. This article discusses important safety and protection considerations when using a lithium battery, introduces some common battery protection ICs, and briefly outlines selection of important components in battery protection circuits. Overcharge