The cost of nickel is an issue… The metals needed to make the battery – nickel and iron – are also more common than, say, cobalt which is used to make conventi

The cost of nickel is an issue… The metals needed to make the battery – nickel and iron – are also more common than, say, cobalt which is used to make conventional batteries. Nickel is running about $20/kg. Cobalt is about $50/kg. But, lithium batteries have very little cobalt, about 5% by weight in a Tesla battery. Nickel iron batteries are about half nickel in rough numbers. Combine in that a nickel iron battery is about 20Wh/kg and Tesla batteries are around 250Wh/kg and you get something like 100 times as much nickel used as cobalt to store the same energy. You can mostly ignore the 2.5x price multiplier at that point. The specific energy differences rule nickel iron out for mobile uses, but it has a lot going for it for stationary. I have looked at it each time my off grid lead acid battery banks expire, the cost has come down over the decades, but not enough to make me switch (freeze tolerance is also an issue in NiFe's favor). But I swear, this is the last half-ton of lead acid batteries I'm hauling out there and back. When these go it's either lithium or nickel even if I have to dig an 8' deep battery vault to keep the lithium's electronics in their operating temperature range.