To add both bypass and blocking diodes for 6 panels you will need 12 diodes in total. We have plenty of Schottky diodes here if you want some, no charge, just PM an address to me so I can send them off.
They are these RS component items https://au.rs-online.com/web/p/rectifier-diodes-schottky-diodes/9033450/

as you can see on the listing, minimum purchase is 500 units. I don't think we are likely to use 500 of the things in this life time, so we are happy to help out anyone who has a need for them.

T1 Terry

That smart diode looks good. However, at AU$6 each x 6 panels, the cost is equivalent to 2 extra 20W panels. I think they would only start to make economic sense when they are priced at around $1, even in the larger panels.

I found two other smart diodes, but the TI one looks best:

LX2410A, Microsemi, 10A IDEALtm Bypass Device, 12.5A, 95mV at 10A and 110°C, 12.5µA of leakage current up to 33V of reverse voltage, DFN:

https://www.microsemi.com/document-portal/doc_download/135254-lx2410a-datasheet
https://www.mouser.com/datasheet/2/268/ds_lx2410a-1592826.pdf

SM74611, Texas Instruments, Smart Bypass Diode, 15A, forward voltage drop of 26mV at 8A, TO-263:

http://www.farnell.com/datasheets/1857934.pdf
http://www.ti.com/lit/ds/symlink/sm74611.pdf

MP6914, Ideal Diode for Solar Panel Bypass, Integrated 5.3mO 30V Power Switch, SOIC8E:

https://www.mouser.com/datasheet/2/277/MP6914_r1.0-526360.pdf

Here is a commercial panel that uses one bypass diode for each solar cell:

REVIEW | AE Solar Smart Hot-Spot Free Mono Series 280 -- 310W:

https://review.solar/ae-solar-smart-hot-spot-free-mono-series/

https://review.solar/wp-content/uploads/2019/05/AE-Solar-Smart-Hot-Spot-Free-Mono-Series-280--310W-Datasheet.pdf

Therefore, what in particular has set the AE Solar Smart Hot-Spot Free Mono Series as a new focal point in industry innovation? Bypass diodes. However, not the typical 3 or 6 bypass diode configuration in conventional solar panel designs of today.

Based on a standard 60-cell module design, the AE Solar Smart Hot-Spot Free Mono Series incorporates a bypass diode at each solar cell. The result, up to 80% more power when shaded compared to standard solar panels and the ability to mitigate the effects of detrimental solar panel hot-spot.

 I had the same idea, but I rejected it because the voltage drop would have been too great. For example, if 10 cells were shaded, then their combined voltage drop would be 4V (= 10 x 0.4V).

 However, here is a paper which uses smart diodes:

 Photovoltaics in the shade: one bypass diode per solar cell revisited:

 https://www.onlinelibrary.wiley.com/doi/10.1002/pip.2898

So I'm guessing that the AE Smart panel uses smart bypass diodes rather than regular Schottky types.

T1 Terry wrote:

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There were panels on the market many moons ago that used this technique, so it's nothing new. The area the panel covered to produce the same output as a panel that didn't have the bypass diodes meant the gains were not enough to make up for the lost harvest area, ...

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 I don't understand. Where were the losses? Was this in the days before ideal diodes? AFAICT, TI announced their smart diode in 2013.

dorian wrote:

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T1 Terry wrote:

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There were panels on the market many moons ago that used this technique, so it's nothing new. The area the panel covered to produce the same output as a panel that didn't have the bypass diodes meant the gains were not enough to make up for the lost harvest area, ...

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 I don't understand. Where were the losses? Was this in the days before ideal diodes? AFAICT, TI announced their smart diode in 2013.

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 Finally got the better of me, I had to Google "AFAICT" to find out what I meant :lol:
I have 2 of these early panels with the bypass diodes between each solar cell/module glued to a sheet of fibreglass and glued onto the poptop of my kombi. they are early semi flexible panels and originally came off the roof of an ex hire Kia transit van The panels are 6v so there are 2 in series, the pair cover an area of 1490mm x 740mm and produced a stunning 64w when new. I haven't actually measured their output for a while, but I can't imagine it has improved with the passing of the last 15 yrs. No doubt the manufacturers name is on the underside of these panels, but I'd have to destroy the panels to get them off the fibreglass, so that's not happening. As a comparison, the semi flexible 100w 12v nom. panels I have here measure 500mm x 1000mm and I'd in no way claim these were the cutting edge as far as area to output ratio.

Maybe the theory doesn't match the reality, but the reality is a fixed thing, so the theory must be missing a few figures in the calculations ......

T1 Terry

After a rethink, it might be only 10 yrs they have been on the Kombi roof, before that we had rigid panels mounted as assort of aerofoil over the roof up front that acted as shade over the windscreen yet had enough clearance behind to allow the poptop to be raised and lowered. They had been recued from a rubbish bin at a CMCA rally in Tassie some 16 or more yrs ago and finally shattered after coping a wave of water thrown up by a truck travelling in the opposite direction. With each of us travelling at around 100km/h, the impact was all too much, but they had been there for probably 5 yrs so they had done a great job. Considering the panels were probably circa 1960's or at the latest '70s, so the technology was not even close to todays, they outperformed these semi flexible shade tolerant panels on the poptop now by a country mile.

-- Edited by T1 Terry on Sunday 17th of November 2019 01:43:41 PM