Patent ID: 8704489
Filing Date: 2014-04-22
Classification: H01M,H02J,Y02E,Y02T

Abstract:
1. A battery system comprising: one or more lithium ion secondary batteries each having a power generating element and an electrolyte being impregnated in the power generating element and containing lithium ions; charge and discharge control means for controlling charging and discharging of each of the lithium ion secondary batteries; and internal resistance detecting means for performing at least one of detection and estimation about a level of internal resistance in at least one of the lithium ion secondary batteries; wherein the charge and discharge control means comprises: a plurality of mode control means for controlling charging and discharging each of the lithium ion secondary batteries on a predetermined charge and discharge condition, the mode control means including: mode selecting means for selecting one mode control means to be used from the plurality of mode control means, wherein the mode selecting means is configured: to select the decreasing mode control means when the internal resistance detecting means detects or estimates that the internal resistance is relatively high; and to select the increasing mode control means when the internal resistance detecting means detects or estimates that the internal resistance is relatively low, and wherein the internal resistance detecting means is resistance correlation physical quantity detecting means for estimating a level of the internal resistance based on a resistance correlation physical quality having a correlation with the internal resistance.