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Fire Proof Wood
03/30/2016 at 12:37 • 0 commentsAnd fire proof batteries.
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Pre Potassiation of Anode Easier Than Once Thought.
03/29/2016 at 03:57 • 0 commentsThats a word I created it.
THE ANODE!!
KOH and SiO2 in water heated to 90 degrees Celsius yields a water soluble compound.
So today I performed these reactions with an excess of SiO2 to decorate the surface of the diatoms with K2SiO3 or K2O•nSiO2
The balanced equation is as such n SiO2 + 2 KOH → K2O•nSiO2 + H2O from wikipedia.
https://en.wikipedia.org/wiki/Potassium_silicate
The K2SiO3 is soluble in water hence the need for an excess of SiO2, this is boiled to dryness and the soluble K2SiO3 will crystallize on the surface of the diatoms.
The best news is it avoids all the patents :)^10
Also I can use the exact same strategy to make Li2SiO3 for which there is no wiki page.
THE CATHODE!!
I heated the dried K2SO4 today in a crucible with the activated carbon to synthesize the K2S. Both these materials need to be combined with carbons(graphene or carbon black)/metal powders to make them conductive. Also an excess mass molarity of sulfur needs to be combined with the K2S. At this point however neither the anode or cathode can come into contact with water as they are reactive and soluble with such.
ELECTROLYTE!!
KNO3 in THF and emulsifier??? I have no idea yet, more later.
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The basis for my strategy
03/22/2016 at 13:10 • 0 commentshttp://pubs.acs.org/doi/abs/10.1021/ic500919e
This paper entails the opposite of what I am attempting.
I will start with a potassiated cathode so the full cell will be discharged upon assembly, this should increase total amp hours per gram as there will be a perfect amount of sulfur compared to potassium in the cathode.
A slight excess of amorphous silica in the anode will give the potassium ions plenty of space to fully intercalate, this is going to be awesome!
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Potassium Sulfate has Arrived
03/21/2016 at 23:35 • 0 commentsAll my materials are here, I just spent a few hours reading about lithium sulfate aqueous electrolytes in AC/AC symmetric super-capacitors. With the addition of potassium iodide they can actually perform as well as exotic organic electrolytes in EDLC super-capacitors.(in energy density not voltage potential)
This is significant as if the K+ cation conductivity is high enough in the neutral aqueous electrolytes they are almost perfect for potassium sulfur batteries. The benefit being poly-sulfides are insoluble in water which will keep them in the cathode where they belong and solve the issues that have plagued lithium sulfur batteries for so long. As the poly sulfides migrate to the anode they cause irreversible capacity fade.
The problem with aqueous electrolytes is that they are limited to around 1.2 volts per cell when they are highly basic or acidic, (exception is lead acid) however being that potassium sulfate or lithium sulfate is pH neutral the cells can operate up to 1.9 volts. Potassium Sulfur batteries are limited to 2.2 volts anyway with any noticeable capacity starting at around 1.9 volts.
One noticable problem is that K2S in the presence of water will form a lewis acid and KOH will be evolved however basic aqueous electrolyte at the cathode does not cause a problem, the evolution of oxygen at the anode is really what limits most aqueous electrolytes to around 1.2 volts.
The first step however is to synthesize potassium sulfide using activated carbon to absorb a saturated solution of potassium sulfate and water then drying in the vacuum oven. This will allow all potassium sulfide evolved from heating to be kept deeply in the pores of the activated carbon increasing conductivity between the insulating sulfur that will evolve upon charging and the carbon backbone that conducts electrons.
This will then be placed in a crucible and heated with a propane torch for 30 minutes. Carbon monoxide and carbon dioxide will evolve so this should be done outside.