Nissan Motor Company Limited

Yuki Takanezawa

Naoki Yamamoto

Atsushi Takano

Takashi Iimori

Kazuhiko Okino

Hisashi Niioka

Kazumi Kaneko

Hirofumi Iguchi

A battery controlleroutputs a voltage sampling and holding command signal to an integrated circuit CCn located at an upstream end of cascade connection of integrated circuits CC-CCn such that integrated circuits CC-CCn sample and hold output voltages of unit cellsgrouped into battery modules M-Mn. The battery controller, after transmission of the voltage sampling and holding command signal, outputs a transmission command signal to the integrated circuit CCn at the upstream end of the cascade circuit to transmit output voltages of the unit cellsheld in the integrated circuits CC-CCn to the battery controller. As a result, a time lag in the detection timings of output voltages of the unit cellsof the battery modules M-Mn can be decreased.

Battery voltage monitoring device

Even when temperature sensors () used in a device for warming a battery () being not in use by using a battery-driven heater () have failed, the battery () is prevented from freezing. Based on a battery temperature (Tb) and an outside air temperature (Ta), times (&#x394;tto &#x394;t) during which Tb will decrease down to a warming start temperature (Tb_start) are each set to the next controller startup time (&#x394;t). A controller () is started up every &#x394;t, at t, t, and t, and checks whether Tb&#x3c;Tb_start is satisfied or not. At twhen Tb&#x3c;Tb_start is satisfied, a heater () is battery-driven to warm the battery (). After twhen the outside air temperature sensor () fails, the outside air temperature (Ta) is set to a fixed value (Ta_const) and based on this Ta=Ta_const and the battery temperature (Tb), the above control is repeated. Accordingly, it is unlikely that the temperature information (Ta) from the outside air temperature sensor () that is at fault causes &#x394;t to become extremely long like &#x221e;, so that it is avoided that the heater () cannot be operated because the controller () cannot be started up and the battery () freezes.

Battery temperature control device

Growing community of inventors

Zama, Japan

Yuki Takanezawa