Polymer coating process for electrode assemblies incorporating ion exchange materials
A method of manufacturing a battery cell includes forming an electrode and coating the electrode with a n-mer solution. The n-mer coated electrode is treated by heat, ultraviolet, or cross linking agents to polymerize the n-mer and form an ion exchange material that covers at least some of the electrode.
1 . A method of manufacturing a battery cell, the method comprising:
forming an electrode comprising zinc particles and operable as a negative electrode in the battery cell;
coating the electrode with an n-mer solution such that the n-mer solution forms a layer over the electrode and at least partially embeds into the electrode after coating the electrode with the n-mer solution; and
curing the n-mer solution thereby forming an ion exchange coating partially embedded into the electrode and contacting at least a portion of the zinc particles of the electrode; and
soaking the electrode with the ion exchange coating in a solution comprising hydroxide anions, thereby at least partially replacing n-mer anions with the hydroxide anions and converting the ion exchange coating into a hydroxide-based ion exchange coating.
2 . The method of manufacturing the battery cell of claim 1 , wherein the n-mer solution comprises at least one of a monomer, an oligomer, a branched polymer, or an unbranched polymer.
3 . The method of manufacturing the battery cell of claim 1 , wherein curing further comprises exposing the ion exchange coating to heat, ultraviolet, or chemical agent thereby inducing crosslinking in the ion exchange coating.
4 . The method of manufacturing the battery cell of claim 1 , further comprising arranging the negative electrode with a positive electrode comprising one or more materials selected from the group consisting of nickel hydroxide (Ni(OH) 2 ), nickel oxyhydroxide (NiOOH), manganese dioxide (MnO 2 ), manganese oxide (MnO), a ferrate salt (Fe(VI)), a manganate salt (Mn(VI)), and a permanganate salt (Mn(VII)).
5 . The method of manufacturing the battery cell of claim 1 , wherein the zinc particles are sized to be less than 300 microns and packed to have a nonzero pore volume less than 50% of total electrode volume.
6 . The method of manufacturing the battery cell of claim 1 , wherein forming the electrode comprises forming an active material layer over a current collector.
7 . The method of manufacturing the battery cell of claim 6 , wherein the current collector comprises one or more materials selected from the group consisting of copper and zinc.
8 . The method of manufacturing the battery cell of claim 6 , wherein the current collector has one or more forms selected from the group consisting of a plate form, a foil form, a mesh form, a porous sponge-like form, a punched metal form, a slotted metal form, and an expanded metal form.
9 . The method of manufacturing the battery cell of claim 1 , wherein the electrode further comprises zinc oxide particles in addition to the zinc particles.
10 . The method of manufacturing the battery cell of claim 9 , wherein the electrode further comprises bismuth oxide (Bi 2 O 3 ) in addition to the zinc oxide particles and the zinc particles.
11 . The method of manufacturing the battery cell of claim 1 , wherein the hydroxide-based ion exchange coating further comprises one or more functional groups selected from the group consisting of sulfonic acid, a quaternary amino group, a carboxylic acid group, a primary amino group, a secondary amino group, and a tertiary amino group.
12 . The method of manufacturing the battery cell of claim 11 , wherein the one or more functional groups of the hydroxide-based ion exchange coating comprise the sulfonic acid selected from the group consisting of sodium polystyrene sulfonate and poly-2-acrylamido-2-methyl-1-propanesulfonic acid (polyAMPS).
13 . The method of manufacturing the battery cell of claim 11 , wherein the one or more functional groups of the hydroxide-based ion exchange coating comprise poly-acrylamido-N-propyltrimethylammonium chloride (PolyAPTAC).
14 . The method of manufacturing the battery cell of claim 11 , wherein the one or more functional groups of the hydroxide-based ion exchange coating comprise carboxylic acid groups.
15 . The method of manufacturing the battery cell of claim 11 , wherein the one or more functional groups of the hydroxide-based ion exchange coating comprise polyethylene amine.
16 . The method of manufacturing the battery cell of claim 1 , wherein the n-mer solution comprises one or more compounds selected from the group consisting of a (3-acrylamidopropyl)trimethylammonium compound, [3-(methacryloylamino)propyl]trimethylammonium compound, a [2-(acryloyloxy)ethyl]trimethylammonium compound, a [2-(nethacryloyloxy)ethyl]trimethylammonium compound, a (vinylbenzyl)trimethylammonium compound, a 2-acrylamido-2-methyl-1-propanesulfonic acid compound, a 3-sulfopropyl acrylate compound, a 3-sulfopropyl metacrylate compound, a diallyldimethylammonium compound, a vinylbenzenesulfonate compound, and a N-(3-aminopropyl)methacrylamide compound.