Silver Cell Parameters - Best practices

[JSRoeth]

This is my first time to post on a subject.
I have followed Sreetips on YouTube and tried to follow his outline for starting up a Silver Cell.

The questions I have are more along the line of Best Practices.
Here are the parameters of my cell's construction:
* My cell is in a 16 liter stainless steel pot
* The total area in square inches (round sides and flat bottom) is 427 square inches
* The Diameter is 11 inches with a 5.5" radius
* I use a Rubber Made basket which is 4.5" x 4.5" x 4" deep
* Holds 4 pounds of cemented to silver popcorn shot.
* The electrolyte is created by using silver cement shot at 150 grams per liter (2,400 grams in electrolyte) with excess silver remaining after cooking until no fumes are present.
* I use the same dacron filter bag that Streetips uses
* The temperature of the electrolyte is ambient which today is 90 degrees
* I wrapped an 8 gauge copper wire around the outside the pot thinking the ground would evenly distribute contact on the upper and lower sides of the stainless steel outside.
* I read in a forum that circulation is a benefit so I placed my cell on my magnetic stirrer and rotate the egg at 200 RPMs.

First Question is about the size of my shot basket. With the volume I have described of my cel, is this basket considered on the small side or does the size of the basket not make a difference?

Second Question: my amps can easily reach 3.0 yet my voltage is at best 1.8 volts, does the size of my cell cause a lower maximum voltage since 1.7 to 1.8 is about all I can register?

Third Question: Would adding heat to the electrolyte improve the performance of volume of crystals generated in a 24 hour cycle?

Fourth Question: Is there a metric a cell operator can expect to generate in weight of crystals generated in a 24 hour cycle? Is this metric a function of amps and volts (if the volume of cell is not a factor) and that 150 grams of silver per liter is the correct base to spin up a cell into operation.

Observation: Cell has been in operation 4 days. A half inch thick band around the top 2 inches is forming crystals yet not getting tree like branches, middle to bottom of sides have similar pattern crystals forming yet at half the thickness which is why I started using magnetic stirring today. Not certain how to classify the crystal yet (Dense, Thin, Spongy).

Guidance and feed back is appreciated, I am certain in one form or fashion some if not all of my questions have been asked before somewhere in the forum yet like a rabbit hole many threads start out promising yet are just that a Rabbit Hole.

 

[g_axelsson]

In theory, current is the only factor that can affect the deposition rate in an electrolytic cell. In practice there might be some side reactions that lowers the effectiveness of the deposition, for example at too high voltages water starts to break down into oxygen and hydrogen. When you see bubbling at the anode and cathode you know you are pressing the cell too hard.

The voltage of a cell is a function of several factors, as the geometry of the cell, agitation, composition of the electrolyte, distance between the electrodes, temperature... and so on. This is why plating power supply can adjust the current. The voltage ends up where it ends up.

So if you want to produce more silver you have to get a power supply that can deliver more current or run it for a longer time.

Göran

 

[kurtak]

In theory, current is the only factor that can affect the deposition rate in an electrolytic cell. In practice there might be some side reactions that lowers the effectiveness of the deposition, for example at too high voltages water starts to break down into oxygen and hydrogen. When you see bubbling at the anode and cathode you know you are pressing the cell too hard.

The voltage of a cell is a function of several factors, as the geometry of the cell, agitation, composition of the electrolyte, distance between the electrodes, temperature... and so on. This is why plating power supply can adjust the current. The voltage ends up where it ends up.

So if you want to produce more silver you have to get a power supply that can deliver more current or run it for a longer time.

Göran

Goran

Per the underlined - in a silver (or copper) parting cell you want to "set" (adjust) the voltage & let the amperage end up where it ends up

Now to address the question from JSRoeth

In a silver cell the general rule of thumb is to "set" you volts somewhere between 3 - 3.5 volts (a copper cell run at "about" half that voltage) running the voltage higher then that can cause co-depositing of other metals once the electrolyte starts becoming corrupted with other metals

Example; - if there is Pd in the anode - Pd &/or Cu will start to co-deposit once the electrolyte becomes corrupted with Pd &/or Cu if you run at a higher voltage

It is the amperage (not the voltage) that determines several factors in the function of the cell such as

the geometry of the cell, agitation, composition of the electrolyte, distance between the electrodes, temperature... and so on

In other words - the amp output of your power supply is what "in part" determines the size of the cell you can run

Amps are also effected by distance between anode & cathode - if you place the cathode (as example) 2 inches from the anode the amps will run higher & the further away you move the cathode the more the amps will drop off - as a rule of thumb you want the distance of anode to cathode to be 4 - 4.5 inches

Again - as a "rule of thumb" you want to factor a current density of about .33 amps per square inch of anode (you want a cathode of "at least" twice the size as the anode - it can be more) the amps will vary as the cell runs - the amps may start at less then .33 when you first start the cell & as the cell nears the end of the run they may go over .33

Example; - if you "set" the voltage output of your power supply at 3 - 3.5 volts & in theory - if you factor a current density of .33 amps per square inch = 3 square inches of anode per amp --- so if the max amp output of your power supply is 10 amps - then in theory you could run an anode 3 inches X 10 inches = 30 square inches --- however - with an anode that size - volts set at 3.5 - & 4 inches between anode/cathode the cell is likely to draw close to the full amps when you first start it & as the crystals grow closer to the anodes - the power supply is going to "want" to deliver more amps - but because the amps are already starting high but wanting to go higher - it "may" cause an over heating problem with the power supply - which "could" lead to short life of the power supply - especially if its a cheap power supply (weak transformer &/or poor heat sink)--- I burned out 2 cheap $100 power supplies before I put out the $1,200 for a "good" power supply (wish I had spent a few hundred more for 30 amp output)

To put it all in perspective - here is a pic of my silver cell - it holds 4 liters electrolyte - distance between anodes & cathode is 4 inches & my power supply is 10 volt 10 amp output - my anodes are 4.25 inches x 1.5 inches - I can put 3 anodes in the anode basket so about a total of about 19 square inches of anode

When I first turn it on the amps start out at about 5 amps - that is a current density of about .26 amps per square inch --- at the end of the run when the crystals are closer to the anodes it will be pulling 9.5 amps if not the full 10 amps which means the current density has gone up to .5 - .52 amps per square inch --- with only 19 square inch of anode

Kurt

P.S. hmmm can't get my phone to connect with my computer in order to down load the pics I wanted to post --- sorry about that

 

[rickzeien]

In theory, current is the only factor that can affect the deposition rate in an electrolytic cell. In practice there might be some side reactions that lowers the effectiveness of the deposition, for example at too high voltages water starts to break down into oxygen and hydrogen. When you see bubbling at the anode and cathode you know you are pressing the cell too hard.

The voltage of a cell is a function of several factors, as the geometry of the cell, agitation, composition of the electrolyte, distance between the electrodes, temperature... and so on. This is why plating power supply can adjust the current. The voltage ends up where it ends up.

So if you want to produce more silver you have to get a power supply that can deliver more current or run it for a longer time.

Göran

Goran

Per the underlined - in a silver (or copper) parting cell you want to "set" (adjust) the voltage & let the amperage end up where it ends up

Now to address the question from JSRoeth

In a silver cell the general rule of thumb is to "set" you volts somewhere between 3 - 3.5 volts (a copper cell run at "about" half that voltage) running the voltage higher then that can cause co-depositing of other metals once the electrolyte starts becoming corrupted with other metals

Example; - if there is Pd in the anode - Pd &/or Cu will start to co-deposit once the electrolyte becomes corrupted with Pd &/or Cu if you run at a higher voltage

It is the amperage (not the voltage) that determines several factors in the function of the cell such as

the geometry of the cell, agitation, composition of the electrolyte, distance between the electrodes, temperature... and so on

In other words - the amp output of your power supply is what "in part" determines the size of the cell you can run

Amps are also effected by distance between anode & cathode - if you place the cathode (as example) 2 inches from the anode the amps will run higher & the further away you move the cathode the more the amps will drop off - as a rule of thumb you want the distance of anode to cathode to be 4 - 4.5 inches

Again - as a "rule of thumb" you want to factor a current density of about .33 amps per square inch of anode (you want a cathode of "at least" twice the size as the anode - it can be more) the amps will vary as the cell runs - the amps may start at less then .33 when you first start the cell & as the cell nears the end of the run they may go over .33

Example; - if you "set" the voltage output of your power supply at 3 - 3.5 volts & in theory - if you factor a current density of .33 amps per square inch = 3 square inches of anode per amp --- so if the max amp output of your power supply is 10 amps - then in theory you could run an anode 3 inches X 10 inches = 30 square inches --- however - with an anode that size - volts set at 3.5 - & 4 inches between anode/cathode the cell is likely to draw close to the full amps when you first start it & as the crystals grow closer to the anodes - the power supply is going to "want" to deliver more amps - but because the amps are already starting high but wanting to go higher - it "may" cause an over heating problem with the power supply - which "could" lead to short life of the power supply - especially if its a cheap power supply (weak transformer &/or poor heat sink)--- I burned out 2 cheap $100 power supplies before I put out the $1,200 for a "good" power supply (wish I had spent a few hundred more for 30 amp output)

To put it all in perspective - here is a pic of my silver cell - it holds 4 liters electrolyte - distance between anodes & cathode is 4 inches & my power supply is 10 volt 10 amp output - my anodes are 4.25 inches x 1.5 inches - I can put 3 anodes in the anode basket so about a total of about 19 square inches of anode

When I first turn it on the amps start out at about 5 amps - that is a current density of about .26 amps per square inch --- at the end of the run when the crystals are closer to the anodes it will be pulling 9.5 amps if not the full 10 amps which means the current density has gone up to .5 - .52 amps per square inch --- with only 19 square inch of anode

Kurt

P.S. hmmm can't get my phone to connect with my computer in order to down load the pics I wanted to post --- sorry about that

Thanks. Very well explained. Hope to see the pics soon!

Sent from my SM-G950U using Tapatalk

 

[kurtak]

Ok here are the pics

 

[rickzeien]

Nice looking cell. It looks like the cathode is held up from the floor with spacers. I have not seen that before. Is it stainless? Does it complicate the harvest?

There is a pipe or rod coming down to it. Is that for the electrical connection.

What are you using for the anode connection? Do you use shot in the anode basket?

Thanks for sharing.

Sent from my SM-G950U using Tapatalk

 

[snoman701]

Nice battery jar! I use them as planters! Lol


Sent from my iPhone using Tapatalk

 

[kurtak]

Nice looking cell. It looks like the cathode is held up from the floor with spacers. I have not seen that before.

Per the underlined - no it (the cathode) is not held off the floor with spacers - however there is a :bit" of a convex to the floor - so "at the edges" it sits a "bit" high so that cause's what is known as the "edge effect" --- this cause's the silver to deposit at bit more at the edges (& a bit of silver - at the beginning deposits down over to the under side of the cathode) there has been discussion in the past about the edge effect & it has been suggested to tape the edge to prevent the edge effect

However - personally - I like the edge effect - why ? --- because the silver tend to deposit a bit more at the edges the crystals tend to grow more dense & larger at the edges - as a result - when I harvest the crystals from the cell I always get some nice large crystal which run from 2 - 7 grams which people that are into crystals are willing pay way more then spot for :mrgreen:

Don't have time to post more right now (got to get ready for work) but here are a couple more pics

Kurt

 

[rickzeien]

Thanks Kurt.

Sent from my SM-G950U using Tapatalk

 

[JSRoeth]

Thank you for the feedback to my question.
I just returned from work travels.
I another question which will be posted under a new thread since it relates to other metals following the silver in the electrolysis process. I will be starting over from scratch and will incorporate the answers in the new and improved cell.

 

[Shark]

I have seen some of Kurt's silver crystals and the wife has a nice specimen as well. The pictures do not do them justice. They are so white they can hurt your eyes under a bright light.

 

[DIY5050]

Is it too simple to ask why my cell keeps growing in one spot with large thin crystals and short the anode? Is it simple geometry? First it was from one side of the bowl, then the other. This morning directly from the bottom. I am using the sreetips method of a stainless bowl, anode basket, and cutting board. PSU is running 3 - 3.3v and current limited to 1.8 amps.

 

[Yggdrasil]

Is it too simple to ask why my cell keeps growing in one spot with large thin crystals and short the anode? Is it simple geometry? First it was from one side of the bowl, then the other. This morning directly from the bottom. I am using the sreetips method of a stainless bowl, anode basket, and cutting board. PSU is running 3 - 3.3v and current limited to 1.8 amps.

You want to run the Voltage as low as possible and let the Amps go free.

 

[FrugalRefiner]

Often, it is the place where the anode and cathode are closest to each other. The current follows the path of least resistance. Depending on how your connections are made, it can also be the area closest to where you've connected to the bowl and/or the anode basket.

Dave

 

[DIY5050]

So I was thinking all 3 times, the "hot spot" was an area near my glass stir rod. To my knowledge, glass is not conductive, however who knows what the Chinese put is these cheap rods. This morning the growth was surrounding the rod and was easy to remove. I have the cell running without the rod sitting inside the bowl. When I get back from work I will see how far I can push the cell with current limit wide open. So how many amps should I run? I ask because running the cell without limit, there will be current flow no matter the voltage. Depends on the impedence (ohms) of the cell.