The famous, charging a phone with lemons myth, myth or not?

[playman]

Hi there folks.

As the title says, can you charge your phone with lemons?
Any one care to answer this? preferably with a detailed on why not or how to.
It may be in series and or parallel, with or with out minimal extra components.

Looking forward for answers
Playman

[mariushm]

Re: The famous, charging a phone with lemons myth, myth or not?

You can make a battery out of anything that has liquid inside which can act as acidic electrolyte.
Lemons, oranges, grapefruits all have citric acid, which works well as electrolyte.
You can also make batteries with potatoes (in case you didn't play Portal 2 already)..

There's a very detailed article on Wikipedia about making batteries out of lemons: https://en.wikipedia.org/wiki/Lemon_battery

Short story : depending on the metals used for the poles, you get a battery with voltage between 0.9v and 1.7v so you can connect 5-6 such lemons in series to have a battery that can output around 5v, which is the voltage the phone expects on the usb connector.

However, the current output is VERY LOW, typically under 1mA - most phone chargers are between 500mA and 1000mA and some high end smart phones could even charge at 1500-2000mA.
Most phones won't even charge if there's less than 50-100mA so basically you'd have to use 2-400 lemons ( lots of sets of 5-6 lemons) connected in parallel to increase current output.

As an alternative, you'd use energy harvesting chips (see http://www.linear.com/products/Energy_Harvesting ) which can capture the energy from the lemons and store it in a supercapacitor or a li-ion battery to make it available for charging a phone for a few seconds or minutes at that 50-100mA or more.

Here's an excellent 1h video about some types of energy harvesting ICs and he also shows how difficult it can be to charge phones with such low current power sources (like lemon batteries, or from temperature differentials when ice melting) : https://www.youtube.com/watch?v=lrELRVFEx_s

[budm]

Re: The famous, charging a phone with lemons myth, myth or not?

You have to ask yourself or do the research about the batteries that you are trying to charge and also go batteryuniversity.com, also search about how to properly charge Li-ion batteries, then you will know what kind of power source capabilty you will need to charge the batteries, how long it will take to fully charge at what amount of current, etc.
Basically knowing what the requirement are first then you find the way to solve the problems at hand and know what can be done or not with what your requirement are, I.E. I want to charge my phone with batteries with lemon in 1hour, what do I need knowing what my batteries requirement are.
As mention above, the current capability of lemon battery is VERY VERY low, you are going to need lots of lemons!

[budm]

Re: The famous, charging a phone with lemons myth, myth or not?

LOL!

https://www.youtube.com/watch?v=Kvqd_M-685U

https://www.youtube.com/watch?v=Ksc6sHxN9H8

I have a nice famous red bridge to sell too, real cheap for those people that saw the videos and believe they are real.

[mariushm]

Re: The famous, charging a phone with lemons myth, myth or not?

Yeah, both fakes

In the first video there's an induction charger under the cardboard (most likely). He just turns on the wireless charger at the same time he plugs the cable in the apple.

In the second video it's even easier, just follow the cable... it disappears behind the desk. There's two cables one unused going into the apple and one going under the desk to the actual charger.

[Per Hansson]

Re: The famous, charging a phone with lemons myth, myth or not?

Hi there folks.

As the title says, can you charge your phone with lemons?

No

Any one care to answer this? preferably with a detailed on why not

Because they don't come with a USB connector and internal battery.

...or how to.
It may be in series and or parallel, with or with out minimal extra components.

Find 4xAA batteries, wire them up in series and insert them into the fruit with a USB connector protruding. (Technically that's only 3 different components).

Looking forward for answers
Playman

You're welcome

[playman]

Re: The famous, charging a phone with lemons myth, myth or not?

Thanks for the replies
The main reason for this question is because a chemical teacher said that it's not possible to charge a phone from lemons, the amperage would to to low
to start a charge, he even had a experiment on a open house day at his school to test this and his experiment showed that it was not possible to do that,
but I doubt that he used more than 5-10 lemons in the experiment.