|
|
BATTERY CONTROL HBB-29 < FUNCTION DIAGNOSIS > D E F G H I J K L M A B HBB N O P BATTERY CONTROL System Diagram INFOID:0000000004212246 System Description INFOID:0000000004212247 BATTERY SMART UNIT • The battery smart unit detects and transmits the HV battery condition signals (voltages, currents, and tem- peratures), which are used to determine charging or discharging values, to the hybrid vehicle control ECU. • The battery smart unit also detects and transmits the cooling fan voltage signals which are necessary to effect cooling fan control, to the hybrid vehicle control ECU. • A leak detection circuit is provided in the battery smart unit in order to detect any excessive current draw from the HV battery. HV BATTERY General • The ALTIMA Hybrid model uses sealed nickel metal hybrid (Ni-MH) HV batteries. The HV batteries have a high power density, are lightweight and offer longevity to match the characteristics of the Hybrid Vehicle Control System. Because the Hybrid Vehicle Control System effects charge/discharge control to maintain the HV batteries at a constant SOC (state of charge) level while the vehicle is operating normally, it does not need to be recharged externally. • The HV batteries use nickel-plated, metal container type cells to realize enhanced cooling performance and a compact construction. As a result, high power density, lightweight construction, and longevity have been accomplished at high levels. • The HV battery unit consists of 34 separate batteries. The batteries each comprise 6 cells and they are con- nected to each other in series through a bus bar module. The cells of the batteries are connected at two locations in order to reduce the internal resistance and improve efficiency. The HV battery unit, which has a total of 204 cells (6 cells ×34 batteries) and a nominal voltage of 244.8 V (1.2 V ×204 cells), is located in the luggage compartment behind the rear seat. • A junction block, battery smart unit and DC/DC converter are used. Integrated into the junction block are an SMRG (System Main Relay Ground), SMRB (System Main Relay Battery) and a current sensor. The battery smart unit monitors the HV battery. The DC/DC converter supplies power to the auxiliary battery after decreasing the nominal voltage of DC 244.8 V supplied by the HV battery to DC 12 V. Power to the JMCIA0081GB |