14.8V 3200mAh 18650 Lithium ion Battery for Medical Equipment, SMBUS

Cell model: 18650/3200mAh/3.7V
Battery specification: 18650-4S1P/14.8V/3200mAh
Nominal voltage: 14.8V
Nominal capacity: 3200mAh
Charging voltage: 16.8V
Charging current: ≤2.5A
Discharge current: 3A
Instant discharge current: 5A
Discharge cut-off voltage: 12V
Internal resistance of finished product: ≤400mΩ
Battery weight: 210g
Product size: 81*76*10.1mm (Max)
Charging temperature: 0～45℃
Discharge temperature: -20～55℃
Storage temperature: -20～45℃
Lithium battery protection: short circuit protection, overcharge protection, over-discharge protection, over current protection, equalization, with SUMBUS communication, etc.
Application field: medical power supply

At present, most of the external interfaces of smart batteries follow the SMBus protocol standard. The smart battery used in this design is a smart battery pack composed of 4 lithium batteries, and the BQ3060 power management chip from Texas Instruments is used for battery management. The BQ3060 chip can manage a battery pack consisting of up to 4 cells, turning an ordinary battery pack into an intelligent battery, and communicating with the processor through the SMBus bus interface.

Mount the MSP430 processor, the smart battery and other peripheral devices on the SMBus bus with pull-up resistors at the same time, as shown in Figure 4. The MSP430 processor is the master and other devices on the bus are slaves. When the transmission protocol is started, the MSP430 can obtain the relevant information of the 4-cell lithium battery through the SMBus bus.

FAQ:

• The relationship between battery capacity and protection board current?
  The capacity of the battery is not directly related to the current of the board. Large capacity does not mean that the battery is large. It mainly depends on the continuous current. That is to say, the larger the motor, the larger the continuous current of the selected protection board, which is not related to the battery capacity.
• How to choose a charger?
  Lithium batteries must use a special charger for lithium batteries. Do not use lead-acid battery chargers. Lead-acid charging may cause high voltage to break down the MOS tube of the protection board, causing the protection board to be overcharged and not protected. Iron-lithium battery charger voltage = battery series number * 3.6V, polymer battery charger voltage = battery series number * 4.2V.
• Is my protective board broken?
  To judge whether there is a problem with the protection board, use a multimeter to check whether the voltage of each string of batteries is consistent? The performance faults with the voltage difference of each section exceeding 1.0V are: not running far, starting power failure, short charging time, basically there are many battery problems. The failure of the protection board is as follows: it cannot be discharged, and the battery has voltage and cannot be discharged.