High-temperature batteries: Correlation
Prices it moves with, and why
High-temperature batteries, such as sodium-sulphur and sodium-nickel chloride, run hot to keep their electrodes molten. They use cheap sodium and sulphur or salt, so cost depends on the ceramic electrolyte, insulation and small production volumes.
Proxy US PPI: storage batteries excl. lead-acid index · monthly, Jan 2006 to Sep 2026There is no free public price for high-temperature batteries itself, so this tab uses the closest public series as a stand-in. Read the numbers as an indication, not as the price of this exact item.
What its price moves with
Selected linkHigh-temperature batteries and Sulfur
Monthly changes -0.01 little or none correlation 12-month changes 0.39 weak correlation Last 5 years -0.12 monthly changes Lead or lag −1 mo High-temperature batteries tends to lead by 1 month (r 0.12) Price function, Jan 2006 to Sep 2026 High-temperature batteries ≈ 44.6 × (Sulfur)0.30 R² 0.17 On this fit, a 10% higher sulfur price goes with a 2.9% higher high-temperature batteries price over the long run. Units: index and index, BLS base period. The fit is loose, so treat the function as a rough guide.Chart: High-temperature batteries and Sulfur prices rebased to 100 at Jan 2006, log scale
Both prices rebased to 100 at Jan 2006, on a log scale so equal percentage moves look the same size.Chart: High-temperature batteries price against Sulfur price, monthly, log scales, with fitted line
Each dot is one month; paler dots are older (2006), darker dots recent (2026); the ringed dot is the latest month. The dashed line is the fitted price function. Both axes are logarithmic.Sodium-sulphur batteries use molten sulphur as the positive electrode. Sulphur is a cheap by-product of oil and gas refining, so it adds little cost, and the sulphuric acid proxy shows no link to the battery proxy, with monthly moves at -0.01.
little or none co-movement month to month · 220 months Show chartsSodium metal and sodium chloride come from common salt, and sodium-nickel chloride cells use salt directly. The salt index shows no clear link to the battery proxy, with monthly moves at -0.07, as salt is a trivial cost.
little or none co-movement month to month · 156 months Show chartsSodium-nickel chloride cells use a nickel cathode, so nickel is their main metal cost. The broad US battery proxy shows no link to nickel, with monthly moves at -0.02 and yearly moves at 0.23.
little or none co-movement month to month · 243 months Show chartsThe beta-alumina ceramic that conducts sodium ions is made from aluminium oxide. Making thin, strong ceramic tubes is the main manufacturing challenge, so cost depends on process yield more than on aluminium prices.
little or none co-movement month to month · 243 months Show chartsCheap LFP has taken most of the grid storage market from sodium-sulphur. High-temperature cells still compete in very hot or cold sites and longer durations. Both share the site's battery index, so no statistics are shown.
Not enough overlapping price history to measure.How to read these numbers
Correlation of monthly changes (the number in the coloured pill) compares how much each price moved, month by month, since 2006 or the first month both series exist. It runs from −1 to +1: near +1 the two usually rise and fall in the same months, near 0 there is no link, and a negative number means they tend to move in opposite directions. Above 0.7 is strong, 0.4 to 0.7 moderate, 0.2 to 0.4 weak.
12-month changes compare year-on-year moves, which shows whether two prices share the same cycles even when the month-to-month noise differs.
Price function is a straight-line fit of the two prices on logarithmic scales: price ≈ k × (partner price)β. β is how much this price moves, in per cent, for a 1% move in the partner over the whole period, and R² is the share of the variation the fit explains. Two prices that both drift up with inflation can fit well without any real link, so read it together with the monthly correlation.
Lead or lag checks whether the monthly correlation is clearly higher when one price is shifted by 1 to 6 months.
Correlation is not cause. The reasons on each card explain the economic link; the numbers show how strongly it has shown up in prices. Proxy series are US producer price indexes or related prices and can blur the real link.
Data: World Bank Commodity Price Data (Pink Sheet), October 2026; US Bureau of Labor Statistics producer price indexes, IMF primary commodity prices and US EIA prices via FRED, Federal Reserve Bank of St. Louis, retrieved November 2026. Calculations by this site.