Researchers at the Harbin Institute of Technology and the Chinese Academy of Sciences have 3D-printed a cement-based supercapacitor directly into a concrete slab, reporting an areal capacitance of 162.14 millifarads per square centimeter while the structure still withstood 23 megapascals of compression, a figure the team says is comparable to commercial concrete used in slabs and stairs. The work, led by Haiping Wu and Jing Zhong with Wencai Ren, is published in ACS Nano.
The printed ink combines cement with carbon black and carbon nanotubes, extruded onto a slab in an interlocking-finger pattern. The two electrode sets never touch; cement between them acts as the separator, with ions moving through the water-filled pores left behind as the cement hydrates. The side-by-side geometry is meant to shorten the distance ions travel compared with layered designs, where ions must cross the material’s full thickness, a problem the authors say gets worse as cement-based devices get thicker.
| Measurement | Value |
|---|---|
| Areal capacitance | 162.14 mF/cm² |
| Energy density | 22.52 µWh/cm² |
| Compressive strength | 23 MPa |
Three of the devices wired in series produced enough voltage to light an array of LEDs. Performance held up under moderate heating and cooling but dropped sharply at minus 18 degrees Celsius, which the authors attribute to freezing interfering with water and ion movement in the pores.
The result follows MIT’s 2023 PNAS carbon-cement supercapacitor and a 2025 follow-up that assembled 12 cells into a 12-volt, roughly 50-farad module powering a fan and a handheld game console. Other groups have combined the concept with 3D printing using carbon-coated nickel foam or printable polymer-modified cement electrolytes; the new paper prints nanocarbon electrodes directly into the cement rather than sandwiching separate electrode layers inside it.
The researchers propose near-term uses in embedded emergency lighting and sensors rather than bulk energy storage, since supercapacitors hold far less energy than lithium-ion batteries by weight.