Diode Bridge Rectifier using Dual Schottkey Diode Bridge
simulate this circuit &ndash; Schematic created using CircuitLab

Figure 1. Centre-tapped energy harvester.

If you double the coil windings you can halve the diode losses as shown in Figure 1. Only one diode will be conducting at any time compared with two on a full-wave bridge.

Since each winding conducts only half the time the wire gauge can be reduced for the same total output power.

It won't hurt to parallel the diodes and may result in ever-so-slightly lower voltage drop.