Power Raspberry PI using Solar Panel

So, here's where I'm at so far.

Even changing to a RPi B+ and using an SDCard, it kept only lasting about 6h.

Last night, I made a change.

I know for a fact that, that a 10.000 mAh power bank lasts all night and still has power left - Using a RPI 4 and an SSD .

But this would imply that I had to disconnect it to recharge. So, I've connected the solar charger to the power bank (to charge it) and the power bank connects to the RPi, like in the picture:

As of this morning, it was still connected.I just tried to open the webpage of the AllSky software and it was loading and I could see the time lapse from last night. I haven't check the charge of the power bank - but I will assume that the solar charger was depleted - last night, around 11pm I went to check and the last led (it has 4 to indicate the charge) was blinking.. I would assume it was odd, but I know that the power bank wasn't fully charge, so it could have been to charge the power bank to the max.

I haven't been home since this morning, but the solar panel should be charging the solar charger and thus charging the power bank and RPi should still be on - When I arrive home will see if this is the case.

I've already ordered some 12.000mAh 18650 batteries to use in the solar charger so I can ditch the power bank (I'm hoping) .

Best regards

feiticeir0 said:

I've already ordered some 12.000mAh 18650 batteries to use in the solar charger

Is that an external battery pack that you plan to plug into the solar charger instead of its internal 3-cell holder ?

It's not a battery pack . Individual 18650 batteries.

They also sell a 10.000mAh solar power manager. It's similar, but you don't have to provide the batteries. - what's inside ?

I bought this one because it was the only one available .

Think you need to explain with annotated photos or diagram (or a web link). It's unclear what you mean regarding individual 18650 cells with 12,000 mAH capability, This doesn't exist.

Shrink-wrapped pack I think without the battery holder

Possibly something like this which is 3x 3500mAh shrink-wrapped

Buy Now

I don't have that one either, just the single cell 14500 (but use an external battery pouch with it) one and the three-cell 18650 one you have.

I might have jumped the gun on this one, but, hey, here it is:

https://www.aliexpress.com/item/32983015969.html?spm=a2g0o.order_list.order_list_main.4.21ef194dQCtjpu

Judging by this review, you will be lucky to get 1200mAh out of these

https://www.youtube.com/watch?v=RtKJFffD0Hw

If you have sourced your 3350mAh batteries from a similar place, then you may want to check them out, as they may be nowhere near their stated capacity either. Especially if your 10000mAh power bank manages to power the Pi 4 all night long, with some room to spare.

There have been battery vendors claiming extremely high capacity values.  The truth is there a limit to the amount of energy that can be stored into a battery, given a certain chemistry and size.  For Li-Ion batteries in the 18650 package, the current maximum is 3600 mAh.  Any advertised value in excess of 3600 mAh is a sham.  Many people, including myself have purchased these so call high capacity batteries only to find that they are nothing but junk.  Not only are they less than the advertised values, but they are also well below the 3600 mAh level.  Don't waste your money on junk batteries.  Buy from reliable sources, and be highly suspicious of any values in excess of 3600 mAh in a 18650 cell.

Thank you all. I'l check them when they arrive. If they are not what they claim, I'll filled a complaint.

Btw, how can i see if the advertised capacity is really what they have? a multimeter ?

There are battery testers that can verify the capacity of a battery.  I have built battery chargers for Li-Ion batteries for products (professionally) and projects (hobby).  One way to verify the capacity of battery is charge a dead battery to full capacity while monitoring the charge current. By totaling the charge current over time you can calculate the capacity of the battery.  The same thing can be done by taking a fully charged battery and discharging it into a load while measuring the current.  Again by totaling the discharge current over time you can calculate the capacity of the battery.

Years ago I posted a blog on a robot project (Walky the Biped Robot - Power pack ) where I charged and discharged a 1200 mAh (14500) battery and discovered that in had a capacity of 210 to 290 mAh. This blog has some more details on the testing of the battery.

Good luck!

Proving it remotely to AliExpress may be hard. They might not accept anything other than evidence from some pro battery test tool. If you can simply cancel the order now, that would be better. Setting it all up and testing them (when you know from fact that they won't support that capacity) is also a waste of your effort surely.

Proving it remotely to AliExpress may be hard. They might not accept anything other than evidence from some pro battery test tool. If you can simply cancel the order now, that would be better. Setting it all up and testing them (when you know from fact that they won't support that capacity) is also a waste of your effort surely.