A stacked lithium battery system

Abstract

The invention discloses a stacked lithium battery system, which includes several lithium battery units connected in parallel, and each lithium battery unit is composed of several lithium battery units with the functions of current balance, backflow protection, short circuit protection, temperature protection and signal transmission. The lithium battery modules are connected in series, and each lithium battery unit is connected to the controller through a corresponding magnetic latching relay. The invention not only has small size and simple peripheral control circuit, but also works stably and reliably, has strong overcurrent resistance, and can directly reduce the existing cost by more than 40%. The present invention can realize lithium battery systems with different voltages and capacities by connecting the required number of lithium battery modules in series and parallel within a certain range, which makes the application of lithium batteries very simple and completely subverts the traditional lithium battery pack. Complicated use methods are extremely important for applications such as electric tools, electric bicycles, electric vehicles, and small energy storage.

Description

technical field [0001] The invention relates to a lithium battery system, in particular to a stacked lithium battery system. Background technique [0002] Today, lithium-ion batteries are more and more widely used in various devices. With the advantages of large capacity and small size, they are gradually replacing traditional lead-acid batteries and are the mainstream of the current battery market. [0003] One of the main technical difficulties in replacing traditional lead-acid batteries with lithium-ion batteries is the need to install over-current, over-charge and over-discharge protection circuits for lithium-ion batteries to ensure the safe operation of the batteries. In mobile phones, electric tools and other application fields, special circuits are used to detect battery voltage, charge and discharge current and other related parameters. When these parameters exceed the limit value, relays, MOSFETs, IGBT and other switching devices cut off the charging and discharg...

AI Technical Summary

Problems solved by technology

At present, the equalization design in the industry basically adopts the bypass resistor mode, which cannot solve the thermal management of the bypass resistor, and may easily lead to safety accidents due to battery overheating. Therefore, it can only be designed at 30-100 mA in general, and there is no practical equalization for large batteries. Effect

Another traditional mode is the energy conversion mode, which releases high-voltage cells to low-voltage cells. Although this method has certain effects, the problem is that when the power lithium-ion battery pack is grouped (series-parallel), the control point There are many, and the management is very complicated. Often, the cost of a battery pack system and the protection system account for more than half of the total cost. Not only is the cost high, there is no scalability, but the design is also complicated and the reliability is low

[0005] In electric tools, electric bicycles, small energy storage and other application fields, a certain number of batteries must be connected in series and parallel to achieve the voltage and capacity required by the application, but the defects of the above-mentioned relays, MOSFETs, IGBTs and other switching devices, and Expensive, complex and unreliable power lithium-ion battery systems greatly limit their application in this field

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