In historical terms, the death of the flint tool, cooking by dung, and other bygone technologies occurred rapidly because several factors conspired to bring in better alternatives. So it is with lead-acid batteries.
This huge industry faces an unspectacular future in vehicles — their main use. Granted, conventional car and truck sales are still increasing thanks to China and other emerging nations, to around 70 million vehicles annually. And there seems to be ongoing use of lead-acid traction-battery power in electric bikes, forklifts, boats, and mobility vehicles for the disabled — say 35 million vehicles yearly. However, every month another threat appears that constitutes a serious nail in the coffin for an industry that has served the world well for over 100 years. Recent examples include:
Stop-start. Automatically switching off the engine when a vehicle stops, however briefly, improves fuel efficiency and reduces emissions. Thus, the use of this technology is expected to surge in the next few years. For urban vehicles with frequent stops, however, lead-acid batteries have difficulty coping, particularly at low temperatures. “Microhybrids” seeking to capture and regenerate braking energy compound the problem. Lithium-ion batteries are, therefore, increasingly preferred.
Electric vehicles. Hybrid-electric vehicles are taking off, particularly industrial and commercial versions. Add to that the Toyota Prius, which is expected to exceed 1 million in annual sales within a few years, along with the huge number of new hybrid and pure electric models becoming available. Forecasts are for on-road hybrids and EVs with modern batteries to comprise 10 to 20% of global production in 2022.
Industrial vehicles. Lead-acid batteries in forklifts seem cheap until you look at their poor performance and painfully short life. Fuel cells and lithium-ion batteries are coming on for indoor electric industrial vehicles as well as outdoor hybrid forklifts and earthmovers, where lead acid is completely unacceptable.
E-bikes. Almost all electric bicycles have lead-acid batteries today, but nearly all of them are in China. Lead acid is almost entirely shunned in other countries because of its heavy weight and poor life and performance. Everywhere, bikes are moving from mainly battery-assisted pedaling to so-called e-bikes and scooters with a throttle. Lead acid cannot keep up with power demands of these larger two wheelers.
Tougher pollution laws. Worse, an increasing number of Chinese cities are banning or severely restricting electric bikes due to accidents, congestion, and improper disposal of lead-acid batteries on more than 100 million electric bikes in use. China wants to leapfrog in technology and there is no leapfrogging with lead-acid batteries. Concerns over pollution from smelting, manufacture, and disposal are driving the Chinese government to cut lead-acid-battery production to 42% of 2010 levels. Few of the 1,930 inspected manufacturers will remain and the many unlicensed sites will be sought out and destroyed. Outside China, ever tougher emission laws impact everything from tugboats to aircraft. Vehicles with lead-acid batteries are increasingly inadequate in addressing those requirements.
Lower costs. Lithium-ion batteries are expensive but their costs will drop by at least two-thirds in the next decade, according to developers, while tiny new range extenders and energy harvesters reduce the size of battery needed.
Supercapacitors. Electrochemical double-layer capacitors have four times the life of rechargeable batteries, tolerate much faster charge-discharge, and use readily available materials. Their self-discharge and energy density have been poor but are improving. Some now hold a charge for a month and have the energy density of a lead-acid battery. Certain electric buses run on supercapacitors alone. Indeed, Elon Musk, founder of Tesla electric car company, thinks supercapacitors are the future, not batteries.
Add in other factors such as the impending use of fuel cells in fleets, battery suppliers and governments focusing their R&D on alternatives, and consumers demanding much better vehicle performance and it’s clear lead-acid batteries will be the losers.
Investors see the lead-acid battery industry as standing on an escalator going down — faster and faster – even though sales statistics have yet to reflect this. Niche markets will remain but clearly, lead-acid batteries are suffering death by a thousand cuts and the end will come more suddenly than most expect. MD
Battery technology will be a key topic at IDTechEx’s upcoming Electric Vehicle conference March 27-29 in San Jose.
Edited by Kenneth J. Korane