MHEV Battery
| ITEM | DESCRIPTION |
|---|---|
| 1 | MHEV battery |
| 2 | MHEV battery cable terminal (positive) |
| 3 | Wiring harness connector |
| 4 | MHEV battery breather pipe connection |
| 5 | Ground cable terminal (negative) |
The MHEV battery is located on the right of the loadspace, behind the right loadspace trim panel. The MHEV battery is mounted in the MHEV battery housing with clamps located by bolts.
The MHEV battery is a sealed unit and cannot be opened. The MHEV battery contains the following:
- MHEV battery modules
- Battery Energy Control Module (BECM).
The MHEV battery module cells are of the Lithium ion type.
The BECM controls the current flow into and out of the MHEV battery.
The MHEV battery has the following connections:
- The MHEV battery cable terminal (positive).
- The ground cable terminal (negative).
- A wiring harness connector for the BECM.
- A MHEV battery breather pipe connection. This allows for pressure equalisation between the inside of the MHEV battery and the outside atmosphere. It also allows gases to be vented to the atmosphere.
The MHEV battery is air cooled with air forced over it by the MHEV battery electric cooling fan. The MHEV battery electric cooling fan is controlled by the BECM.
Battery Energy Control Module
The Battery Energy Control Module (BECM) controls the current in and out of the MHEV battery. The BECM monitors the following to make sure that the MHEV battery operates within normal operational limits:
- MHEV battery modules internal temperatures
- MHEV battery module voltages.
The BECM has the following wiring harness connections:
- Power supply from the Rear Junction Box (RJB).
- High Speed (HS) Controller Area Network (CAN) power mode zero systems bus (quantity 2).
- Power Mode 6 signal from the Body Control Module/Gateway Module (BCM/GWM).
- Pulse Width Modulation (PWM) signal to the MHEV battery electric cooling fan.
The BECM communicates with the Powertrain Control Module (PCM) through the HS CAN power mode zero systems bus. The PCM controls the Belt Integrated Starter Generator (BISG) to charge the MHEV battery when electrical energy is required. The BISG uses energy from the following to charge the MHEV battery:
- Recovered energy when the engine overruns.
- Torque from the engine.
The BECM also controls the power available from the MHEV battery for the following:
- BISG for auto stop/start engine starts and engine assist to increase fuel economy.
- For additional information, Refer to: BELT INTERGRATED STARTER GENERATOR
- Direct Current to Direct Current (DC/DC) converter.
- For additional information, Refer to: DIRECT CURRENT TO DIRECT CURRENT CONVERTER
- Electric supercharger.
- For additional information, Refer to: TURBOCHARGER
The BECM contains a relay, which de-energizes when the power supply from the startup battery is disconnected. This isolates the MHEV battery from the MHEV battery system, without having to remove any MHEV battery cables.
The BECM controls the MHEV battery electric cooling fan with a PWM signal. The duty cycle of the PWM is used to request the required cooling from the MHEV battery electric cooling fan.