Wind-up generators and Li-ion batteries

Thread Starter


Joined Nov 20, 2020
Tl;dr: Are putting Li-ion batteries in a Wind-up flashlight a thing? If not, what options are there for a more reliable, renewable light source?

Hello, I'm a Paramedic, husband and father of a small family of 3. We don't make much money and live in an area where we are often heavily impacted by storms, severe weather, due to living in an old neighborhood in a forested area with above-ground power, as well as civil unrest due to covid and stupidity. I'm trying to improve our families emergency preparedness as we have repeatedly had real emergencies crop up leaving us without power, water, or food for 5-10 consecutive days, multiple times this year. During this time, i pulled out the old wind- up flashlight only to find that the old nickle metal hydride batteries would no longer hold a charge. Though I recently ordered a generator, I couldn't afford a very large one, and I still need a way to power lights in rooms that aren't powered. So I looked to find some wind-up flashlights that used Li-ion instead of Ni-MH but came up empty.

I am admittedly of a limited education and am not familiar with the quirks of different battery types. Is it not possible to engineer a wind-up Li-ion flashlight?

Please help me understand, I wouldn't be bothering you guys with my (most likely) infantile questions, but my family's wellbeing is on the line, and I don't know anyone who has knowledge of this subject.

Thanks in advance.

Audioguru again

Joined Oct 21, 2019
A Lithium battery MUST be charged properly with a charger circuit designed for it to avoid an explosion and/or fire.
Read about it at .

A Lithium battery is killed if you allow its voltage to run down too low so a circuit must detect a low voltage and warn you before it shuts off before the battery is killed.


Joined Aug 7, 2008
Shucks, I thought that I had one, but it is hand crank radio and or flashlight, another or- 3 AAA alk. The other Hand crank radio charges a spring, no batteries.


Joined Oct 2, 2009
We had extensive power outage this past week. The best advice I can give you is be prepared in multiple ways for redundancy. Here is a list of things for such emergencies:

- Multiple 12V sealed lead acid batteries salvaged from previous items, make sure they are topped up regularly
- 12V car battery that still have some life left
- 12V LED lights powered from above
- Camping fuel stove
- Camping fuel lantern
- BBQ with side burner that can be used for boiling water and cooking
- spare propane gas tanks
- battery operated radio
- multiple Li-ion flashlights
- 12VDC to AC inverter
- small 1kW generator
- multiple tanks of potable water
- non-perishable food supplies
- personal supplies, first aid kit and prescription medicine

Audioguru again

Joined Oct 21, 2019
I guess I am lucky that my Canadian electricity was designed with backups so that it is very reliable.
The rare times we have an outage then everybody cheers.


Joined Apr 3, 2014
We had a three day outage in 2003 when Hurricane Isabel passed over us. Completely trashed the power lines with trees tossed all around. My youngest son still needed a nightlight at the time so we brought in one of the solar yard lights. It was one of the cheap ones that stakes into the ground. It was enough power for most of the night and at least allowed him to fall asleep. He just had to remember to take it back outside to charge in the morning!