2
(Ni- Cd) and lead-acid batteries. These recycling programs are very successful in
most developed nations, but unfortunately are not in many developing countries [3,
4]. Going forward from 2015, the emergence of large-scale applications of 100 kWh
to 100 MWh for electric vehicles (EVs) and grid-scale energy storage created predictions that the global market for batteries will exceed 2000 GWh (~40 billion kg)
per year by 2030 [5, 6]. This enormous increase in production creates an urgent
need to address issues of sustainability. For example, the eventual maximum global
market size for batteries will likely top 500+ GWh per annum [7], (Jaffe et al. 2016),
with current technology would require ~100,000+ metric tons of lithium per year,
an amount three times the current lithium global production rate [8], and which
would create overall supply chain material flows on par with the global automobile
industry. Therefore, the mining, processing, and recycling of rare elements for
future battery production becomes an important issue. Government regulation, life
cycle assessments, and recycling strategies should be developed for handling sustainability issues such as greenhouse gas emissions, landscape and mining impact,
toxics release, and fire/industrial safety [9].
Battery system cost is analogous to sustainability when full life cycle costs are
considered. As of 2019, the cost of greenhouse gas emissions and avoidances are
not factored into battery prices, nor are the recycling or end-of-life costs, but, as a
rough approximation, battery system cost is a convenient indicator of the resources
needed for production, and it is certainly the most important metric for short-term
market sustainability. Estimates of the battery system cost needed to achieve profit
in common electrical grid applications are given by Eyer and Corey [7], showing
costs must be well below $100 per kWh for most industrial or utility applications,
and as low as $20 per kWh for transmission congestion relief. The technology
development curve for lithium ion is now widely expected to level off near $300 per
kWh by 2020 and perhaps to $200 per kWh by 2030 [10, 11], meaning that lithium
ion will not be financially positioned to serve most grid applications. Figure 1 shows
cost estimates of aqueous Mn-Zn and Ni-Zn [12–15], could reach below $50 per
kWh suggesting they are perhaps the most sustainable battery chemistry, at present
date of 2019. Mn-Zn batteries also show superior fire safety and toxicity risks,
which will be discussed later. Ni-Zn is of interest as a proxy study for Mn-Zn, so
will be discussed in this chapter. Zinc-air and zinc-bromine batteries are not considered here due to their lack of demonstrated cycle life at industrial scale or in industrial settings. Aqueous silver oxide (Ag-Zn) and nickel metal hydride (Ni-MH)
batteries with very high cycle life and energy density (e.g., [16]) will not be considered here due to the high cost of silver and nickel. An important point made throughout this chapter is the importance of academic researchers to be practical and
transparent, to disclose mAh/mL cycled and mAh-lifetime/mL (or per gram) with
the full materials used, not a subset. Cost models to accurately show $/kWh and $/
kWh-lifetime are also important. To highlight the great interest in these chemistries
in recent years, Fig. 2 shows the intensity of research literature on Mn, Zn, and Ni
battery systems.
D. E. Turney et al.
(Ni- Cd) and lead-acid batteries. These recycling programs are very successful in
most developed nations, but unfortunately are not in many developing countries [3,
4]. Going forward from 2015, the emergence of large-scale applications of 100 kWh
to 100 MWh for electric vehicles (EVs) and grid-scale energy storage created predictions that the global market for batteries will exceed 2000 GWh (~40 billion kg)
per year by 2030 [5, 6]. This enormous increase in production creates an urgent
need to address issues of sustainability. For example, the eventual maximum global
market size for batteries will likely top 500+ GWh per annum [7], (Jaffe et al. 2016),
with current technology would require ~100,000+ metric tons of lithium per year,
an amount three times the current lithium global production rate [8], and which
would create overall supply chain material flows on par with the global automobile
industry. Therefore, the mining, processing, and recycling of rare elements for
future battery production becomes an important issue. Government regulation, life
cycle assessments, and recycling strategies should be developed for handling sustainability issues such as greenhouse gas emissions, landscape and mining impact,
toxics release, and fire/industrial safety [9].
Battery system cost is analogous to sustainability when full life cycle costs are
considered. As of 2019, the cost of greenhouse gas emissions and avoidances are
not factored into battery prices, nor are the recycling or end-of-life costs, but, as a
rough approximation, battery system cost is a convenient indicator of the resources
needed for production, and it is certainly the most important metric for short-term
market sustainability. Estimates of the battery system cost needed to achieve profit
in common electrical grid applications are given by Eyer and Corey [7], showing
costs must be well below $100 per kWh for most industrial or utility applications,
and as low as $20 per kWh for transmission congestion relief. The technology
development curve for lithium ion is now widely expected to level off near $300 per
kWh by 2020 and perhaps to $200 per kWh by 2030 [10, 11], meaning that lithium
ion will not be financially positioned to serve most grid applications. Figure 1 shows
cost estimates of aqueous Mn-Zn and Ni-Zn [12–15], could reach below $50 per
kWh suggesting they are perhaps the most sustainable battery chemistry, at present
date of 2019. Mn-Zn batteries also show superior fire safety and toxicity risks,
which will be discussed later. Ni-Zn is of interest as a proxy study for Mn-Zn, so
will be discussed in this chapter. Zinc-air and zinc-bromine batteries are not considered here due to their lack of demonstrated cycle life at industrial scale or in industrial settings. Aqueous silver oxide (Ag-Zn) and nickel metal hydride (Ni-MH)
batteries with very high cycle life and energy density (e.g., [16]) will not be considered here due to the high cost of silver and nickel. An important point made throughout this chapter is the importance of academic researchers to be practical and
transparent, to disclose mAh/mL cycled and mAh-lifetime/mL (or per gram) with
the full materials used, not a subset. Cost models to accurately show $/kWh and $/
kWh-lifetime are also important. To highlight the great interest in these chemistries
in recent years, Fig. 2 shows the intensity of research literature on Mn, Zn, and Ni
battery systems.
D. E. Turney et al.