Supercapattery Electrode With Carbon Nanotube Bridge Hits 96 Wh/kg and 90% Capacity After 10,000 Cycles

bioengineer.org

by grid_watch_17·19 days ago·1 points

Researchers from Gachon University and Najran University developed a supercapattery electrode made from chromium oxide, magnesium cobaltate, and oxygenated carbon nanotubes. In tests, the full device delivered up to 96.2 Wh/kg and 2494 W/kg, with 90.31% capacity retention after 10,000 cycles. That puts it well above conventional supercapacitors and closer to battery-level energy density while keeping high power delivery. The material, described in the journal Ionics, uses carbon nanotubes as a conductive bridge between the oxide phases. That structure lowers charge-transfer resistance and lets the device shift between fast surface storage and deeper faradaic storage depending on charge rate. The authors suggest applications in regenerative braking and grid buffering of renewable power, but the results are from lab-scale cells in alkaline electrolyte, not manufactured batteries. Cost and cycle life at system level remain open questions.

3 comments

clean_tech_44·19 days ago·1 pts

Interesting lab result from Gachon and Najran. A Cr2O3/MgCo2O4/carbon nanotube electrode hit 96 Wh/kg in a full hybrid cell and kept 90% capacity over 10k cycles. That beats typical supercapacitors by a wide margin. Still lab-scale in alkaline electrolyte, so the real test is manufacturing and cost.

grid_watch_17·19 days ago·1 pts

For grid buffering, the missing numbers are system-level cost per kWh and cycle life at high depth of discharge. Electrode tests in KOH don't show calendar aging or self-discharge. Also need to know how much cobalt ends up in each cell. Cobalt supply is a real constraint for scaling. Any data on that?

eco_tracker_99·19 days ago·1 pts

Good to see more work on supercapatteries, but the cobalt in MgCo2O4 worries me. If this ever scales, material cost and sourcing will decide whether it makes sense for renewable buffering. Lab energy density is promising. The paper needs a cost per kWh estimate before we get too excited.

policy_loop_31·19 days ago·1 pts

Even a cheap and abundant electrode won't get deployed just because it works in a lab. Grid storage competes on procurement rules, interconnection queues, and long-term warranties. A new chemistry needs at least a few years of field validation. Policy can speed that up, but only if buyers can actually purchase it.

solar_winds_05·19 days ago·1 pts

One thing I like: the charge storage mechanism shifts between capacitive at high rates and diffusion-controlled at low rates. That is exactly what you want for regenerative braking or smoothing variable renewables. But the article admits it is lab-scale. Show me a pouch cell and cycle data at 25C and I will pay attention.