Quality Solar Panels to charge Xiaomi 10400 banks?

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power911
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Quality Solar Panels to charge Xiaomi 10400 banks?

I’m curious on what I can get as I tend to charge my devices a lot.
If solar is a way to save, I guess it’s worth spending some cash?

As I live in Malaysia, the sun is not a problem as I get a lot of intense light every single day.

“Have you forgotten about all those who called you a Bringer of Woe and hunted you like an animal?”
“Normal humans don’t go around killing people and burning towns!”
“Don’t worry. I’ll go with you! So you just follow me and no arguing, okay?”

Pavithra_uk
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I made similar setup

45W used solar panel (output only ~20W)
LM2596 Stepdown power module set to 5V out

gadabout
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I think it very unlikely that you will save money by buying solar panels to charge your power banks.

I don't know what you pay for electricity over there but when you do the math, you'll find it much cheaper to just charge them from the wall outlet.

However, for fun, for camping, for emergency backup in an outage - a couple of small USB panels will be a nice hobby investment.  Lots of different brands - the more expensive such as Powerfilm, Brunton and Goalzero will in general be better made than the cheaper ebay equivalents.  If you plan to use your power banks a lot, I'd figure on about a 20W panel for each so that you could almost charge them in a day.

Note that the small backpackable folding panels favoured by hikers and other lightweight travellers will eventually fail due to fatigue at the wire connecting the different sections.  It typically would take many years if you only use them occasionally but may happen much sooner if you are using them every day.  

The larger rigid panels are mostly designed for 12V systems or grid tie and will generally require a charge controller and 12V SLA battery to which you then connect an adapter to charge your power bank.

All of this stuff costs more money than your AC power but it's fun to tinker with. 

A simple search for "solar charging" will net you a number of useful threads.

http://budgetlightforum.com/search?q_as=solar%20charging

Werner
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The cheapest way is a solid panel, a 12V and some dozens of W behind a stepdown Module like KIs33whatever from ebay.

The Foldable panels like the 20W xdragon some here have can charge with 1-1.5A but are indeed a lot more expensive. It will never reinvest because lifetime electricity for a power bank only costs cents…

itsonlyme
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Julian illett on YouTube has some great electronic videos which may give you some inspiration. Most of what he tests is powered off solar charged batteries.

breinrules
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Note though that xiaomi powerbank circuit is not designed for usb solar charging as explained in a slightly old post. 

gadabout
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breinrules wrote:

Note though that xiaomi powerbank circuit is not designed for usb solar charging as explained in a slightly old post. 

 

With a a sufficiently powerful panel and good sun it should be ok.  On a dull day with with a low-power panel or with poor voltage regulation it may not charge properly.

They are not suited as a buffer between the panel and another device for days with passing clouds.

power911
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so I’m guessing the safest bet is a 12V panel with a stepdown just for enough power to recharge the bank?

seems like that’s the only way for a charge via sun.

With gadabout advice, it kinda makes me realize I am not saving much power at all :~
At most I could only save like a few cents even in a long run.

Banggood link to solar power bank

I saw this and thought it would be a nice idea to charge my xiaomi powerbanks with solar.
Then I realize no panels are small enough to deliver enough juice to charge the powerbank within 8 hours unless it’s a 12V massive solar panel.

Doesn’t sound too convenient.

I’ll have to thank you all for saving me some bucks on this.
I’ll stick to the reliable wall outlet

“Have you forgotten about all those who called you a Bringer of Woe and hunted you like an animal?”
“Normal humans don’t go around killing people and burning towns!”
“Don’t worry. I’ll go with you! So you just follow me and no arguing, okay?”

gadabout
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Stay away from the little power banks with the dinky panel fixed to one side. The inbuilt panel is so small as to take days to put any kind of charge into the pack.

In addition, these units are often low quality with vastly overrated mAh claims.

Lastly, heat is the enemy of lithium rechargeables so having this pack sitting out in the sun for hours in a vain attempt to charge it it is just killing the batteries even sooner.

Luminous
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You might justify the cost if it’s large enough for charging other items, like cell phones or even laptops/tablets. A single panel or group around 100W total and 12V deep cycle battery. Could pick up a small inverter. Install a 12V cigarette plug to the deep cycle battery with a dual USB adapter. Can use an old extension cord from the solar panel(s) inside to the battery. Just make sure you get the positive and negitive sides correct.

The cheapest way is to get a USB adapter for the car and charge all your stuff driving around.

Or charge it at work…

You need more charging power than you think, or the cells inside the 10400 bank will end up weak over time.

Lonelydad
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Sad to say, but unless you live off of the power grid, no solar panel today is cost competitive with power from the grid. We are getting there, but not yet.

Yet, many of us have solar panels of one kind or another. Chris Garrett at CPF is looked upon as one of our gurus when it comes to solar. He lives in a hurricane prone area, where power outages can last days, if not weeks. I myself have an Anker 15w portable panel just so I can charge my power banks if we lose power. Normally, if the power goes out it is just an hour or two. About three years ago we had a major ice storm, and some places were out for a week.

When my lose power, my process is to shut down my desktop PC completely, along with anything else plugged into my UPS except for my DSL modem and WiFi router. I figure with those alone on the UPS, I should be good for about 30 hrs of connectivity for my tablet. I have the solar panel to recharge my power banks as I use them for lights and a fan, and a kerosene heater if it is winter. I also have lots of blankets. Knock on wood, I think I'm set.

You don't really need a parachute to skydive. But you DO need one if you want to skydive twice!

willie
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Use to run several solar hog hunting lights. Used 20w to 48w panels to 12v deep cycle batteries. Used solar charge/light unit to run 365. Saw this on ebay with USB that would be a one unit does all. 120v inverters are impractical for solar use on this level.

http://www.ebay.com/itm/Intelligent-10A-30A-PWM-Solar-Panel-Charge-Controller-12V-Auto-Battery-NEW-/381476834519?var=&hash=item58d1ca8cd7:m:mJUd76xr5aHVJ6u4hPOLVlA

And this

http://www.ebay.com/itm/10A-12V-24V-Auto-Switch-PWM-Solar-Panel-Battery-Charge-Controller-Wit-5V-USB-UPC-/301562670888?hash=item4636892f28:g:eXIAAOSw7aBVA9xH

hank
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Quote:
Stay away from the little power banks with the dinky panel fixed to one side.

Amen. I had one of these a couple years ago thinking it was a good earthquake-kit thing.
Noticed a few months ago that the case had popped open.

When I looked I found the battery (pouch type) puffed up like a balloon, that’s what popped the case open.
This is the Battery University picture of that happening:

http://batteryuniversity.com/_img/content/pack7(1).jpg
“Ballooning indicates that the manufacturing process may have been flawed.”

I’ve been wondering if I can at least salvage the solar panel and charger circuit for a 3v LiFePO4 cell.