1, lithium battery boost test

First, let the lithium battery through the buck chip down to 3.3V, and then to the microcontroller and Bluetooth module power supply, another intended to rise to 7V to take a load.

Results: Bluetooth module does not work, and the search does not work. Remove the Bluetooth, the microcontroller and the load are working properly. When the microcontroller is removed, Bluetooth and the load work properly. When not using buck and giving a set of power supply alone, all three work normally.

Note: buck with the xc6206 boost with the fd6291.

2, lithium battery boost and buck problems

The following to analyze the causes of the above problems, to find the lithium battery cell voltage rise and fall common failures of the problem, to learn together.

Lithium-ion battery monomer voltage has a certain range, such as the normal operating voltage range of lithium iron phosphate batteries is 2.5V-3.65V, lithium manganate and the normal operating voltage range of ternary batteries is 3V-4.2V.

Lithium-ion batteries in the application, when the total voltage of 60V and below, the need for battery protection board. 60V above, the need to use the battery management system (BMS). The role of these two devices to protect the battery to work properly.

Note that, after the number of strings in the battery pack is set, the battery pack voltage can not be adjusted at will. That is, the battery pack voltage changes can only be within the normal operating voltage range: when charging, from the lower voltage limit up to the upper voltage limit. When using electricity, it goes down from the upper voltage limit to the lower voltage limit.

Understand the problem, if you want to make the lithium battery lift voltage range is large and can be adjusted at will.

The best solution: make a good set of battery pack, with a suitable inverter, and then a DC regulator, you can meet the requirements of the lithium battery boost and buck.

Note: This method is rarely used in practical applications, unless the AC power used is often blacked out, or when using solar or wind power to charge the battery pack, this method of boosting and bucking will be considered.

The above method of boosting and bucking of lithium batteries can be used in the test and used to study and learn the effect is good.