Browse Prior Art Database

Control Method of Battery Temperature during Quick-Charging

IP.com Disclosure Number: IPCOM000014492D
Original Publication Date: 2000-Oct-01
Included in the Prior Art Database: 2003-Jun-19
Document File: 2 page(s) / 58K

Publishing Venue

IBM

Abstract

Disclosed is a method of thermal control to reduce the battery temperature rise during quick charging. This method would be applied to a NiMH battery, a Li-Ion battery and any other batteries. The battery temperature rises as the charging current increases. This battery temperature annoys the user because the user feels uncomfortable by the heat of the battery being charged. The present method eliminates this situation by stopping charging battery at the MaxT as shown (Fig.1). This method consists of 3 control parameters, (a) MaxT which means the maximum temperature to stop charging battery, (b) MinT which means the minimum temperature to start charging battery, and (c) dT/dt which means temperature rise per a certain duration of time. MaxT is decided optionally and set to the EEPROM inside the battery pack. MaxT is lower than TCO(Thermal Cut Off) temperature. The purpose of MaxT is to avoid heating human body, such as fingers or laptop, by battery temperature rise. MinT is lower than MaxT. There is a hysteresis, temperature delta, between MaxT and MinT to stop/start charging battery.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 68% of the total text.

Page 1 of 2

Control Method of Battery Temperature during Quick-Charging

  Disclosed is a method of thermal control to reduce the battery
temperature rise during quick charging.

   This method would be applied to a NiMH battery, a Li-Ion
battery and any other batteries. The battery
temperature rises as the charging current increases. This
battery temperature annoys the user because
the user feels uncomfortable by the heat of the battery being
charged. The present method eliminates
this situation by stopping charging battery at the MaxT as
shown (Fig.1).

     This method consists of 3 control parameters, (a) MaxT which
means the maximum temperature
to stop charging battery, (b) MinT which means the minimum
temperature to start charging
battery, and (c) dT/dt which means temperature rise per a
certain duration of time.

   MaxT is decided optionally and set to the EEPROM inside the
battery pack. MaxT is lower
than TCO(Thermal Cut Off) temperature. The purpose of MaxT is
to avoid heating human body,
such as fingers or laptop, by battery temperature rise. MinT is
lower than MaxT. There is
a hysteresis, temperature delta, between MaxT and MinT to
stop/start charging battery.

     The flow chart is shown as (Fig.2). The charging battery
stops every time the temperature
of battery reaches MaxT. The charging battery re-starts after the temperatu
The charging start/stop repeats between MaxT and MinT until dT/dt is detect
or peak voltage detection or any other mehtods can be used as a charging co
as dT/dt detection.

The advantag...