[scarenoob]

I bought two lanterns to be used for Halloween.

I didn't like the single led light so I decided to remove the whole led light + solar controller.

So the upgrade go from 1.2V Ni-MH to 3.7V Li-ion stepping up to 9V.

Parts:

• TP4056 lithium Ion battery charging modules
• 1N5408 Diodes
• 14500 3.7V Lithium Ion Protected Batteries (AA size of 18650)
• Step-Up Voltage Regulator (9V - U3V70x family)
• Black Vellum Card Stocks 54lb Transparent (Samples)
• Red/Black 24AWG? Stranded Wires
• 2 Pin Waterproof Connectors
• RF Wireless Remote LED Controllers

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I got the idea from this guy

The TP4056: Lithium Ion/polymer Battery Charger IC

Learn how to use the TP4056 properly. There's a right way, and a wrong way, to use it to safely charge Lithium Ion batteries.

www.best-microcontroller-projects.com

Tp4056a Li Ion Battery Chargingdischarging Module| Components101

components101.com

TP4056:
The one bad thing about the module is that it doesn't have a automatic switch controlling the OUTPUT.
Options:
1) A simple hack as shown in the video above.
2) Add a switch like BJT Transistor or MOSFET.

I have tried using BJT Transistor but unfortunately it suck down volts (voltage drops from 3.7V to @ 2.4V).

14500 Batteries [AA Lithium] | Battery Junction

Save money and go rechargeable! 14500 batteries are lithium AAs designed to fit most household electronics. The cell size you need at a price you'll love, browse 14500 batteries at Battery Junction.

www.batteryjunction.com

Pololu - Step-Up Voltage Regulators

Boost converters generate a regulated output voltage that is higher than the input voltage.

www.pololu.com

Ebony Black Vellum Card Stock - 8 1/2 x 11, 54lb Colors Transparent - LCI Paper

This black transparent paper is the heavyweight 53lb / 200gsm counterpart to our translucent Ebony (10) from the Gmund color system transparent collection. Although this is twice the thickness of the standard 100GSM translucent this would still be considered lighter than card stock. Use for...

www.lcipaper.com

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^ The original solar controller

^ A simple "hack" for automating switch.

 

[scarenoob]

Left: Orange | Right: Red

 

[scarenoob]

Updates: Oct 22, 2020

#1 - Solar chargers I have put together (using the hack as shown in the video above) didn't work as I expected. They worked fine when I tested them in the garage but when left outside, they didn't switch ON at night. After investigating the switching problem, I have discovered that solar panels were still charging (anywhere 0.2V to 2V) even at night.

#2 -
So I had to start over again and decided to give the MOSFET a chance again. After searching on Google, I found someone tried to build a similar solar charger setup. Based on that person setup, I found out what is the MOSFET I should be using. I ordered 3x NDP6020P (P Channel) MOSFETs from digikey.

https://electronics.stackexchange.com/questions/442898/p-or-n-channel-mosfet-to-disconnect-a-load

MOSFET - NDP6020P ON Semiconductor | Discrete Semiconductor Products | DigiKey

Today, they arrived. I took apart (removed the hack) one of the solar chargers and put in the MOSFET. Now the solar charger seem to be working as should. The only issue I have now is the switching is not instant (OFF/ON). Not 100% perfect but it works.

Since I currently have 3 MOSFETs, I have fixed 3 out of 7 solar chargers. Will have to order more to fix the rest.

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Oct 28, 2020

Here's the final (hopefully!) modification: