The Antimony Price Rise Crisis – a Lower Cost Pathway for Lead-Acid Batteries – 21st Asian Battery Conference and Exhibition

The Antimony Price Rise Crisis – a Lower Cost Pathway for Lead-Acid Batteries

Microtex batteries like all industrial lead acid battery companies has been hit by rising material and energy costs. By use of sound metallurgical principles and understanding of battery chemistry from pasting through to formation, they have enabled sufficient cost savings to overcome the additional antimony costs and have become even more competitive in today’s markets. The higher antimony price since last year, can more than double the average positive tubular plate cost. Removing or reducing antimony in industrial positive grids presents problems of material strength with implications for processability, corrosion and cycle life. In order to find alternative alloys, it was necessary to make a detailed examination of the metallurgy of the mechanisms of creep strength, UTS and YS in order to enhance the properties of alternative, lower cost lead-based alloys.
Detailed processing and performance trials were performed using these principles to enable new lower cost alloys to be substituted by changing processing methods. These include:
Metallurgical: Casting conditions, post casting treatment, effects of flash drying and curing on mechanical properties. UTS and YS measurements of new grid alloys.
Electrochemical: Capacity tests, positive grid corrosion.
Mechanical properties of new alloys were enhanced to match or exceed existing Sb alloys. Energy savings of around 5% were recorded for the VRLA formation process.

A detailed review of the metallurgical and electrochemical principles that affect the processing, plus in-service characteristics, and subsequent results are also included.
Additional work on reducing energy formation costs by up to 15%, particularly by applying new, more efficient formation principles to VRLA batteries, are discussed.

Results include:
Formation energy with new algorithms, mechanical properties of grid alloys, capacity and corrosion tests.

Further work:
Refinement of alloy secondary elements and further investigation of VRLA electrolyte resistance mechanisms to reduce propagation of parasitic reactions.

Presenters

Dr Michael McDonagh

Chief Technical Officer, Microtex Energy

Graduated from Nottingham University with a PhD in Metallurgy and Materials science. Worked in industry in the field of battery design and manufacture, mostly in the motive power and industrial energy storage sector at director level. Built 3 lead acid battery factories.
R&D includes development of a high temperature lithium/iron-sulphide battery for the Trident nuclear submarine. Was also engaged by Ebonex as head of manufacturing for a bipolar lead acid battery.
Won 2 SMART awards for MF LAB batteries, London Underground and British Rail in the early 1990s. Won an EU funded contract under the PHARE programme to supply train starter and lighting batteries to SNCFR (Romanian rail). In 2014 won the EU gold seal of approval for fast, low energy charging of LAB fork lift truck batteries. Awarded a Horizon 2020 grant.
Over the past 25 years, worked as an international consultant. Clients include: Zibo, Chilwee, SEC, Jinkelli, Microtex, Unik, Shield batteries, and TBS UK. Expert testimony in legal disputes including: Anti – Terror squad in Manchester and a dispute between Iran and the USA – Court of International Justice, Hague.