Browse Prior Art Database

LI-ION/NIMH Quick Charge System in Notebook PC

IP.com Disclosure Number: IPCOM000115317D
Original Publication Date: 1995-Apr-01
Included in the Prior Art Database: 2005-Mar-30
Document File: 2 page(s) / 72K

Publishing Venue

IBM

Related People

Narita, I: AUTHOR

Abstract

Disclosed is a system for charging the battery which is exchangeably installed into the Notebook PC. According to the subject invention, the system can charge both Li-ion and NiMH battery. The system comprises the variable Constant Voltage Constant Wattage Constant Current (CVCWCC) AC/DC adapter [*] and the controller of it. The variable CVCWCC AC/DC adapter is the AC/DC adapter which can vary its output characteristics by the external signal. Li-ion battery is very sensitive to the over charging voltage, and therefore it has the properties with regard to the charging voltage and the current. Also, NiMH battery has the properties with regard to the charging current. By this charging system, the controller controls the AC/DC output characteristics that conform to the properties of charging of the respective battery.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

LI-ION/NIMH Quick Charge System in Notebook PC

      Disclosed is a system for charging the battery which is
exchangeably installed into the Notebook PC.  According to the
subject invention, the system can charge both Li-ion and NiMH
battery.  The system comprises the variable Constant Voltage Constant
Wattage Constant Current (CVCWCC) AC/DC adapter [*]  and the
controller of it.  The variable CVCWCC AC/DC adapter is the AC/DC
adapter which can vary its output characteristics by the external
signal.  Li-ion battery is very sensitive to the over charging
voltage, and therefore it has the properties with regard to the
charging voltage and the current.  Also, NiMH battery has the
properties with regard to the charging current.  By this charging
system, the controller controls the AC/DC output characteristics that
conform to the properties of charging of the respective battery.  As
a result, Both Li-ion and NiMH battery can be charged by only one
system.

      Fig. 1 shows the circuit implementing the subject invention.
The main battery is charged by the AC/DC adapter while the SW1 is
switched on by the charge controller.  The output voltage/current
level of the AC/DC adapter is controlled by the CV control signal and
the CC control signal.  The CV control signal determines the CV
domain of the output of the AC/DC adapter, and the CC control signal
determines the CC domain of the output of the AC/DC adapter.  The CV
domain and the CC domain are different between Li-ion and NiMH
battery.  The V[ref]  selector and the I[ref]  selector select the
reference voltages for the CV control signal and the CC control
signal respectively.  While the NiMH battery is charged, the NiMH
battery's V[ref] and I[ref]  are selected...