Three phase bridge rectifier used in a single phase input supply

Have you ever thought a 3 phase bridge rectifier can be used in a single phase input supply? Yes that is possible. But one can ask himself what about the other phase and the two remaining diodes? As we know in a single phase only 4 diodes are used to convert AC to DC and in this case we will be using Live and Netrual on Va and Vb inputs conducting D1 and D4 on the positive cycle and D2 and D3 on the negative cycle. What about D5 and D6, why not use a simple single phase bridge rectifier? Remember in this case, this application is used where we need to charge the batteries. Now under normal conditions when the input supply is on, the AC to DC convertion is done using the rectifier and at the same time charging the batteries. In this case D6 is used to charge the batteries through the charger card from positive to negative of the battery. In case of the rectifier failure or AC input failure, we will depend on the batteries to still supply the load where the direction of current will change from negative to positive through D5. In conclusion, D6 will be used for "charging" of the batteries where as D6 will be used when the batteries are "discharging" (AC input has failed). In case of a three phase input supply where all the 3 input are used, a separate diodes will be used for discharging and charging of the batteries (A semi pack / thyristor module can be used for this function).