Many existing battery systems use high-cost materials and exotic metals in their electrolyte and battery hardware design. Also, the energy storage materials in batteries are toxic, environmentally hazardous, and flammable (lithium, bromine). Lignin is a naturally occurring biopolymer which accounts for approximately 30 wt% of all wood biomass. Various types of lignin are extracted from wood as part of the pulping process in paper manufacturing and are considered a low-value byproduct that is often burned for disposal and waste heat recovery purposes. Lignin has seen limited precedent as an energy storage material and has never before been used in a flow battery system.
Technology Overview
Northeastern researchers have formulated a liquid lignin-containing battery electrolyte and used it to store energy via a highly reversible redox reaction in the lignin molecule. When formulated, the lignin molecule contains multiple phenol groups, that can be loaded into the half-cell of a flow battery and exposed to sufficient electric potential to release electrons and hydrogen ions from these phenol groups. The loss of these electrons and hydrogen ions will form quinone groups, thus altering the potential of the lignin electrolyte, and therefore leaving it in a “charged” state. Reversing this reaction will return the lost electrons and hydrogen ions back to the lignin electrolyte, thus reforming the phenol groups and “discharging” the system. 
- The invention is cost-effective as‑
     - Low manufacturing cost as abundantly available materials are used
     - Low cost of battery hardware to store energy 
     - Inexpensive dialysis membrane is required 
     - Inexpensive catalyst is required for battery operations
- It allows for independent scaling of power and energy 
- Environment friendly 
- Grid-scale energy storage
- Micro-grid power
- Backup power
- Remote location power
- Electric grid demand response
- Renewables integration
- Frequency regulation
- License
- Partnering
- Research collaboration
Patent Information:
For Information, Contact:
Mark Saulich
Associate Director of Commercialization
Northeastern University
Hongli Zhu
Jonathan Hamel