Charge Holders...

Hi guys, I am generating some power via piezio-electric means (about only 0.4W of power) and I am wondering how to charge up a battery using this low power. I am wondering about the feasibility of using capacitors as a temporary charge holder, but am not very sure what chip or setup can be used to ensure that the energy is not lost. Any suggestions?

Thanks in advance.

Cheers!!
Appleon

So is this 1000 volts at 400ua, or 10v at 40ma, or...?
What does the waveform look like? Is it sinusoidal, or impulses, or...?

The waveform...

The waveform is somewhat a sine curve, and the +ve peak is about 20V while the -ve peak is about -40V. Since the current as a result is quite small, won't charging a capacitor fully be slow? Thanks.

Cheers!!
Appleon