Possible encapsulation material?

[Mike90250]

.....
Here is a question I would like to have answered. What would be the effect of Sylgarding the cells to the glass untabbed? Would the heat required to solder them after the cells were attached damage the Sylgardf? This would be an effort to eliminate warping of the cells caused by the soldering action.

How do you attach the tab wire to the fronts ?

Possibly tab front an back of each cell, leaving a short stub, clean cells, then "dip" each cell 100 % into sylguard? That would coat each one, you could solder the tabs, and then encapusulate the rest with nearly anything clear, as long as the initial sylguard dip was good.

[Calgirl]

Why not use the Sylgard on the front of the cell only, paint a thin film on the surface of the cells on an entire stringer and then lay the cells on the glass in a rocking motion until they are flat. Work hard to keep the bubbles out. Let them dry with weights to hold the entire string completely flat on the surface of the glass, perhaps use the L brackets of a future panel to do this.

But now the backs of the cells are not sealed. Use another cheaper substance to seal the back side where UV and clairity are not required. Here almost anything will work, plastic, paint, varnish or many other substances. Take great care not
not to choose a substance which will corrode the wires and connections connecting the cells. This might streach a quart of Sylgard so that a quart could concievably complete three or four panels. This would indeed be a major saving in the construction of the panels.


wayhopper

Why not do all solder work, then paint back (blue side) and the tabs with Sylgard and let dry BEFORE laying down on the glass? Make certain to cover tab wires. For added insurance and to make the cell string stick to the front glass, you could run a line of Sylgard on glass where cells will be prior to placing the cells on the glass. After dry, paint/spray backside with whatever substance suits your fancy. Just make sure to cover all wires, all the way around.

Check string with volt/amp meter at each step.

[the pu man]

There is one major flaw with this process. If you simply use the Silicone on the front and then look to use something cheap on the back how are you going to 'adhere' another encapsulant to the silicone? Very few products actually adhere to silicone. You also run the risk dependent on the other material of all the problems listed prior IE making sure you pick something that is not going to react with the silicone, making sure the expansion and contraction charateristic of the 'other encapsulant' is similar to ensure you dont get a split line between the two materials as the panel expands and contracts with temperature ranges. If a split line does occur then it will actually draw moisture in as it expands and contracts.

Water will always find a way through so having an interlayer of two differing types of materials runs a far higher risk of failing than sticking to just one. Also remember that contary to popular view on silicone they are actually porous so the thinner the coating the higher the potential the moisture will ingress through.

Coming from an electronics and electrical potting and encapsulation background I have never seen any success in trying to use silicone in conjunction with another material. You are simply adding a variable into the process which opens up far more knock on issues than if you had just spent the money in the first place.

[Calgirl]

Very good point....thanks.

[elect41]

Self leveling encapsulation mix

Hey guys,

Want some advise,solar encapsulation product aeromarine300-21 its suppose to be self leveling

http://www.jgreer.com/pages/pdf/30021-tds.pdf

[Bigbirdd]

IS Ecapsulation needed o

There is one major flaw with this process. If you simply use the Silicone on the front and then look to use something cheap on the back how are you going to 'adhere' another encapsulant to the silicone? Very few products actually adhere to silicone. You also run the risk dependent on the other material of all the problems listed prior IE making sure you pick something that is not going to react with the silicone, making sure the expansion and contraction charateristic of the 'other encapsulant' is similar to ensure you dont get a split line between the two materials as the panel expands and contracts with temperature ranges. If a split line does occur then it will actually draw moisture in as it expands and contracts.

Water will always find a way through so having an interlayer of two differing types of materials runs a far higher risk of failing than sticking to just one. Also remember that contary to popular view on silicone they are actually porous so the thinner the coating the higher the potential the moisture will ingress through.

Coming from an electronics and electrical potting and encapsulation background I have never seen any success in trying to use silicone in conjunction with another material. You are simply adding a variable into the process which opens up far more knock on issues than if you had just spent the money in the first place.

Hi this bigbirdd All I have read about encapsulation is done on the back of the cells. I use duel pane glass windows and mount my cells seal the back.during hot Idaho summers I have on voltage loss. So how will encapsulation benefit me.Right now i don't encapsulate my cells I run silicone on the cells not crossing the tabbing . I then silicone the outer edge place backing to silicone area than seal backing with urethane. Its work so far I have a panel I built last year its been through rain ,snow .

[the pu man]

Hey guys,

Want some advise,solar encapsulation product aeromarine300-21 its suppose to be self leveling
http://www.jgreer.com/pages/pdf/30021-tds.pdf

This product would give far better UV stability over a standard Epoxy clear system agreed however if you check through the data it is a rigid system - a major no no. If you used this type of system during cycling it would crack and probably crack the cells as well. Any encapsulant used needs to have flexibility so that it can expand and contract without causing stress fracture.

[elect41]

Thanks again guys,

Your information has helped me,it seems that sylgard its the best choice.
Very helpfull

Thank you.

[grayski41]

encapsulation

Hi all,
im new here an to solar panel construction, I have made one panel with no encapsulation and now busy making 6 more, Alliminium frame and backing with plexiglas front, I intend to lay the cells in the frame held in place with a little silicone and then paint the cells with slygard or equivilant, I have been told i can reduce costs and bubbles by thinning the slygard with xylene and only painting a thin layer on the front only, and use a cheaper acetoxy silicone thinned with xylene on the back of the cells before placing in the frame... any ideas/ thoughts would be welcome

[russ]

Hi grayski41 - Welcome to Solar Panel Talk!

One of our DIY types should be along with a comment before long.

Russ

[Bigbirdd]

Mike90250 fused pane

You talked about fused panel how do I do it. or rather what do I use.

[Jeffc]

I came across this forum while looking for a cheap way of encapsulating my panels.---Glad I did!

I have five 60W panels up on my roof at present ,two have been up for about 18 months ,three for about six months.

None have any encaptulation. ( Gasps I hear ) It was only supposed to be temporary , but I left them up there !

I needed a system in place in order to apply for ROC before the 31/3/2010 deadline.

All the panels are holding up well despite braving all the elements , although there is a lot of condensation in the panels which is not good.

I was encouraged to see the video with the guy applying Silgard , but was dismayed at finding out the cost.

I thought the bulk of the cost of making the panel would be the cells , now at approx

[Calgirl]

Why not dip the entire string in Sylgard, and then hang it up to dry by the tab wire? That way you cover the entire cell and almost all wiring at much less cost than painting the glass front and then painting the back of the cells and wire, or pouring the encapsulant. A little Sylgard touch-up after strings are re-located and re-soldered in the panel and you have a panel of cells and all wiring well protected.

Another approach would be to lay the dipped string down almost immediately on the glass so that you have a seal between the glass and the cells to prevent moisture getting between the Slygard protected cells and the glass.

Since the Sylgard covering on the backside of the cell would be pretty thin, I would apply a thin cover on the panel back....one that allows for heat dissipation and air circulation. The backside cover is only to give a little mechanical protection to the cells, etc.

[DeltaFox 25]

Have you ever worked with sylgard???? I have and it's a very thick substance.
I don't think you could coat them and hang them up to dry. and the wireing would be weakend also. Good luck to you if you can do that..Why don't you put the sylgard down then put the cells down then cover the rest with the rest of the sylgard. do this all at once. O Don't forget the backing.

[Jeffc]

Polysulphide Sealant

From Datasheet-

POLYSULPHIDE SEALANT is a one component, gun applied, synthetic rubber based sealant which cures by absorption of atmospheric moisture to form a permanently flexible seal. It is suitable for use within the construction industry on all joints where above average repeated movement is encountered over a wide temperature range. It provides outstanding resistance to weathering and chemical attack from solvent, alkalis, dilute acids, oils and grease.

This is the stuff that is used to seal double glazing units.


How about applying a bead of this around the perimeter of each cell onto the glass. Notice it cures by absorption of atmospheric moisture so any moisture between the cell and glass will be absorbed in the curing process.

Here is a link to the data of a product sold in UK.

http://www.kingfisheruk.com/specs/data/polysulphidesealantpds.pdf

It has very good U/V resistance and 20+ yrs service life. Oh and it