Bio-ionic liquid hydrogels and use of same
The present invention relates in part to a polymer functionalized with a bio-ionic liquid to form a gel electrolyte. The gel electrolyte thus formed is biocompatible and biodegradable. In certain embodiments, the electrolyte is used for making implantable 3D printed energy storage devices.
1. An energy storage device comprising:
at least one electrode comprising a laponite and graphene hydrogel mixture,
wherein the at least one electrode is in electrochemical contact with a gel electrolyte,
wherein the gel electrolyte comprises a polymer functionalized with a bio-ionic liquid (BIL), and
wherein the polymer comprises gelatin methacrylate (GelMa) or poly(ethylene glycol) diacrylate (PEGDA).
2. The device of claim 1 , wherein the BIL comprises choline.
3. The device of claim 2 , wherein in the BIL the choline is conjugated with an acrylate or methacrylate group, which is covalently bound to a methacrylate group on GelMa or an acrylate group in PEGDA.
4. The device of claim 3 , wherein the BIL comprises choline acrylate or choline methacrylate.
5. The device of claim 1 , wherein the ratio of BIL and polymer in the functionalized polymer is about 1:4 (w/w) to about 4:1 (w/w).
6. The device of claim 1 , wherein the electrolyte comprises about 10% to about 30% (w/v) polymer.
7. The device of claim 1 ,
wherein the electrolyte comprises about 5% to about 20% (w/v) BIL or
wherein the electrolyte has a porosity ranging from about 10 μm to about 80 μm.
8. The device of claim 1 ,
wherein the electrolyte has an elastic modulus of at least about 200 KPa.
9. The device of claim 1 , wherein the at least one electrode is at least partially interdigitated with another electrode.
10. The device of claim 1 , wherein the at least one electrode consists of a laponite and graphene hydrogel mixture.
11. A method of forming the energy storage device of claim 1 , the method comprising independently printing the gel electrolyte and the electrodes using extrusion-based 3D printing.
12. The method of claim 11 , wherein forming the gel electrolyte comprises contacting the polymer with the BIL in the presence of at least one photoinitiator.
13. The method of claim 12 , wherein the at least one photoinitiator is selected from the group consisting of eosin Y, 2-hydroxy-2-methylpropiophenone, 2-methyl-4′-(methylthio)-2-morpholinopropiophenone, lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP), 2-hydroxy-4′-(2-hydroxyethoxy)-2-methylpropiophenone (Irgacure) and hydroxymethyl-propiophenone (HEMP).
14. The method of claim 11 ,
wherein the gel electrolyte comprises about 10% to about 20% (w/v) BIL or
wherein the gel electrolyte comprises about 10% to about 30% (w/v) polymer.
15. The method of claim 11 , wherein the gel electrolyte comprises about 1:4 to about 4:1 (w/w) BIL to polymer.
16. The method of claim 11 , wherein the photoinitator comprises about 0.5% (w/v) of the gel electrolyte.
17. The method of claim 11 , wherein at least two electrodes are at least partially interdigitated.