ARNO

In recent years, the lead-acid industry has come through with another great innovation, the advanced “lead-carbon” design. This new battery uses carbon to reduce sulfation in the negative plate to expand the cycle life of flooded and VRLA batteries under high rate pulse cycling at partial state of charge. With this dramatic improvement, an advanced lead-carbon battery can now equal the performance of nickel-metal hydride (NiMH) and lithium-ion (Li-Ion) batteries, but at far lower cost.

If our carbon-based materials has been added to the Negative & Positive Active Material (NAM & PAM) during paste preparation in a variety of forms including MWNT and exfoliated graphite based graphene structures, when incorporated at 0.1-0,8% w.r.t. lead oxide, carbon increases the charge acceptance of a battery by more than 200% but at the cost of paste rheology and paste density. Reductions in paste density directly lead to increased active material adhesion to the grids, increased battery capacity with no requires of higher active material masses to reach specification, and sufficient cold-cranking performance.

Since the technology for the production of such batteries has long been developed and well known, and the need to create reliable home and semi-industrial backup power sources capable of interacting with primary sources (such as, for example, solar panels, wind turbines or city networks at night) with increased charging and discharging resource and increased capacity - more relevant than ever before - our team, in cooperation with KAKST and the Bulgarian Academy of Sciences, managed to develop a technology for the use of carbon nanomaterials in the production of lead-acid batteries (without changing the technology for the production of power sources themselves) and create a pilot sample of this kind devices.
As a result of the work carried out, a storage device was created on the basis of modified lead-acid batteries with a negative plate changed by adding carbon nanomaterials, equipped for further testing with an inverter for converting solar energy and a special stand for testing the device under various charging-discharging modes under various environmental conditions.
The peak power of the secondary power supply on 16 batteries with electronic control of the common power bus was, according to the specification, 15 kW, the standard power was 9 kW, which made it possible to speak of the installation as a prototype of a real industrial product. At the same time, the number of charging-discharging cycles has increased in comparison with conventional power sources by 30-40%, the depth of charging by 10-15%, the output power of each individual element by 10-15%. The stand shown in the picture is not a part of the prototype, unlike the inverter located on the same rack, and is a sample testing device equipped with power management and parameter recording software of our team's own development.