Blue Current's compact, silicon elastic composite battery cells

Blue Current imagined the future battery and is working to deliver it with three critical performance vectors.  The first is to enable the highest possible silicon content to maximize energy density. The second is that the battery must cycle well at low operating pressure reducing the need for extra packaging material. The third is that it must be safe as measured by the thermal stability of the battery materials at high temperatures. Blue Current believes that it is the first to deliver on all three of these metrics using what it refers to as a silicon-first approach with elastic composite electrolyte technology.

Blue Current scientists examining data at a computer

Blue Current's Silicon Elastic Composite Battery

an example showing the cathode, silicon anode and electrolyte in Blue Current's battery technology

Solid State Anode

10x higher silicon content

Full Chemistry System

Enables high performance, low-pressure operation

Composite Separator

Thin composite separator


Optimized for fully dry operation

Delivering on All Three Vectors of Future Battery Performance

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10X Silicon Content

for Energy Density

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Low Operating Pressure

1 MPA for Improved Packaging

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Fully Dry Chemistry

for Safety

Combining Polymers and Ceramics to Enable Silicon

Blue Current combines compliant polymers for adhesion and elasticity with ceramics for ionic conductivity. Electrolyte particles are tied to the silicon particles by strands of polymers, preventing additional SEI formation. Polymers also constrain swelling of the active material, enabling the silicon particles to cycle at low pressure without expanding dramatically.  Traditional solid electrolytes lack elasticity leading to the need for high operating pressure to prevent swelling of the battery cells.

  • Blue Current elastic composite electrolyte particle
  • Traditional solid electrolyte particle
  • Silicon active material particle

Silicon-first Design

Silicon is one of the most abundant material on earth. It also stores ten times more lithium ions than traditional graphite anode materials. With our silicon elastic composite technology we’re able to achieve over 1000 cycles using 10x more silicon than state of the art lithium-ion cells, thus reducing the thickness of the anode by 50% and creating a path to 1000 Wh/L.

a chart display cell operating pressure @ C/5, ranging from 40MPa at 1000+ cycles in 2018 to

Low Operating Pressure

For fully dry ASSB to be commercially viable, operating pressure needs to be become irrelevant. Customers tell us that this should be no more than 1.0 – 1.5 MPa for EVs and 0.1-0.5 MPa for devices – similar to the pressure in a bicycle tire. We’re already testing cells below 1 MPa and we plan to continue driving further pressure reductions over time.

discharge capacity chart showing how liquid electrolytes with high silicon content diminish more quickly than state of the art lithium-ion cells, which in turn deplete more quickly than Blue Current's technology.

Safe Chemistry

Our multilayer cells have been tested by an independent 3rd-party lab using nail, crush and overcharge testing. This testing showed no thermal runaway, venting or ejection of internal materials. We are encouraged by these results and plan to scale our safety tests as our pilot factory is built.

side by side graphics displaying disastrous effects of a nail test on a lithium-ion battery versus Blue Current's technology

High Volume Manufacturing

Our full dry chemistry can be produced using the same high-volume manufacturing equipment currently used in lithium-ion pouch cell production. This includes mixing, coating, calendaring and stacking. Unlike traditional battery production, we do not require the costly steps of formation and aging, which are assumed to be roughly 5% of the overall cost of a traditional LIB battery cell.

The proposed work is scientifically meritorious and revolutionary.
US Department of Energy