Recent developments in bipolar lead-acid battery technology at TNO

The bipolar lead-acid battery currently tested at the Pulse Physics Laboratory and under development at TNO Environment, Energy Research and Process Innovation, is an excellent candidate for pulsed power applications that require multiple high power and high current pulses. At the Pulse Physics Laboratory, the combination of such a battery (as a primary energy source) and an inductor (pulse transformer) is investigated as an intermediate energy storage and pulse forming component. For this application, a battery is required that can deliver currents up to tens of kA's (peak power of tens of MW's) and energy extraction times of tens of milliseconds.
A research programme is being performed in order to better understand and improve the functioning of the fast-discharge bipolar lead-acid battery. Recent efforts directed towards the improvement of the electrode substrate materials for the bipolar plate has resulted in a patent been taken out on a corrosion free nonmetallic substrate. Improvement of the specific power and energy and optimisation of the construction of the bipolar lead-acid battery has led so far to working 12V bipolar battery prototypes using paste technology and with a specific power of 750 W/kg, at a discharge rate of 230 W/Wh using a pulsed discharge current.
In order to operate this type of fast-discharge lead-acid battery reliably and repetitively, a battery management system that controls all cells individually was developed at the Pulse Physics Lab. Furthermore, to test the performance of the battery, a programmable electronic load was built that can sink currents up to 10 kA. The amplitude of the discharge current is controlled by a computer and follows a programmed current-time profile.