Battery protection board introduction

Battery protection board, as the name suggests, lithium battery protection board is mainly for rechargeable (generally refers to lithium battery) to play a protective role of the integrated circuit board. The reason why lithium battery (rechargeable) needs protection is determined by its own characteristics. Because the material of lithium battery itself determines that it can not be overcharged, overdischarged, overcurrent, short circuit and ultra-high temperature charge and discharge, lithium battery lithium components always appear with a protective board with sampling resistance and a current insurer.

Definition

The protection function of the lithium battery is usually completed by the protection circuit board and the current device such as PTC or TCO. The protection board is composed of electronic circuits. It can accurately monitor the voltage and charge and discharge of the battery at -40°C to +85°C. The current in the loop controls the continuity of the current loop in real time; the PTC or TCO prevents the battery from being damaged in a high temperature environment.

The protection board usually includes a control IC, a MOS switch, a precision resistor and an auxiliary device NTC, an ID memory, a PCB, and the like. The control IC controls the MOS switch to conduct under all normal conditions, so that the battery core communicates with the external circuit, and when the voltage of the battery core or the loop current exceeds the specified value, it immediately (tens of milliseconds) controls the MOS switch to turn off, protect the safety of the battery core.

NTC is the abbreviation of Negative temperature coefficient, when the ambient temperature rises, its resistance value decreases, lets electric equipment or charging equipment to react in time, control internal interruption and stop charging and discharging.

The ID memory is often a single-line interface memory, and the ID is the abbreviation of Identification, that is, the meaning of identification, and stores information such as the type of battery and the date of manufacture. Can be used to trace the product and limit the application.

PTC is the abbreviation of Positive Temperature Coefficient. In the professional, the positive temperature coefficient device is usually referred to as PTC. In the battery product, the PTC can prevent the high temperature discharge of the battery and the unsafe large current. According to the voltage, current density characteristics and application environment of the battery, the PTC has special requirements.

PTC is a very important component in battery components and has an important mission to the safety of batteries. Its performance and quality are also an important factor in the performance and quality of battery packs.

When the protection board protects a single battery core, the protection board design will be relatively simple, and the technical high point is, for example, the voltage platform problem that needs attention in the design of the power battery protection board. The power battery is often required to use a large platform voltage in use. Therefore, when designing the protection board, try to make the protection board not affect the voltage of the battery discharge. Therefore, the requirements for the control IC, precision resistors and other components will be very high. For multi-battery core protection board design, there are higher technical requirements, and products with different degrees of complexity are designed according to different needs.

Main technical features:

1. Overcharge protection
2. Over discharge protection
3. Overcurrent and short circuit protection

Solution after mobile phone battery boot protection:

1. Charge directly on the mobile phone with the original direct charge, and the protection circuit of the battery protection board will be automatically opened.

2. Short circuit the positive and negative terminals of the battery in an instant, just see a spark on the electrode sheet, try several times, and then charge it with direct charge.

3. Find a 5V DC power, touch the positive and negative poles of the battery with positive and negative poles, try several times, and then charge with the original charger.