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ELECTRIC VEHICLE BATTERY PERFORMANCE that follows the battery. This approach eliminates the recalibration and configuration of the charger with new charging data profiles based on manufacturer, new/old battery chemistry, and compatibility. Charging of a battery with minimal built-in intelligence is quite analogous to an infant being fed by its mother. The reaction of the infant during feeding determines whether or not the mother provides additional food. On the contrary, the intelligent battery can inform the charger as to how much additional charge or discharge is required to maintain optimal performance of the traction battery. The battery diagnostics information is transmitted using the smart HSD bus. The diagnostics battery pack information sent to the BMONs includes battery type, serial number, manufacturer’s name, and manufacturer’s date. In addition, EV service stations can download battery pack charging data. This data is useful to locate the fault and initiate a corrective action for: • •
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Conditioning or repair of battery modules Replacement of faulty battery components, including connectors, fuses, and wiring Replacement of an entire battery module
In addition, the intelligent battery pack information sent to the BMONs includes battery cycle count, vehicle driving profile, or driving pattern.
HIGH-VOLTAGE CABLING AND DISCONNECTS EVs have two different wiring systems: high-voltage and low-voltage. The high-voltage wiring system is used primarily to provide energy to the motor to propel the vehicle. However, some vehicle manufacturers use high voltages to power heating/cooling systems, power steering pumps, and EV sensors. The Society of Automotive Engineers (SAE) has specified that orange cables are the standard color for high-voltage wiring in EVs. At present, EVs have high-voltage systems ranging from 250 to 360 V DC and in some cases even higher. The high traction voltages are provided by battery packs composed of dozens of individual batteries wired in series and sealed in protective cases. A separate 12 V auxiliary battery is part of design. This auxiliary battery is used for accessories such as vehicle instrumentation, lighting, and HVAC. A separate 12 V battery is kept charged by a DC-to-DC
