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Liions for "high tech" single cell flashlights - to protect or not to protect
Some years ago Liion powerd LED flashlights had very simple buck converters, and of course we equipped them with protected Liions. Protection from overdischarging, protection from overcharging in terribly regulated chargers (my first wolf-eye charger had 4.5 V standby voltage), protection from short circuit. Avoiding a thermal runaway with exploding flashlights, fire and toxic gases.
Nowadays we have perfectly fine regulated single cell flashlights with voltage cutoff at 2.5 - 2.9 V, reverse polarity protection and thermal regulation. Look at Zebralight, for example. And we have chargers that limit the charging voltage at 4.2 V. So can't we say it is "safe" to use unregulated Liions there?
(Please remember: I'm ONLY talking about lights equipped with one single cell, of course. Using unprotected cells (no matter of primary / rechargeable) in series is a risk and should be avoided in any case!)
At the moment I'm using both, surely only high quality brands. Protected AW3400 and unprotected Panasonic 18650B. Same cells, the unprotected are cheaper and are providing a little bit more capacity.
Of course I'm taking care that they never will catch heat, frost, water or damage. I'm storing them one by one in tough plastic containers, so they are safe from short circuit. And I'm exchanging them after 2 or 3 years.
In theory, when you look at a light like the SC600 L2, the only failure where a protected Liion gives us additional protection is an internal short circuit inside of the flashlight. Caused by an electronic failure, by some kind of misassembly in the factoring process, caused by... whatever.
What do you think?
Some years ago Liion powerd LED flashlights had very simple buck converters, and of course we equipped them with protected Liions. Protection from overdischarging, protection from overcharging in terribly regulated chargers (my first wolf-eye charger had 4.5 V standby voltage), protection from short circuit. Avoiding a thermal runaway with exploding flashlights, fire and toxic gases.
Nowadays we have perfectly fine regulated single cell flashlights with voltage cutoff at 2.5 - 2.9 V, reverse polarity protection and thermal regulation. Look at Zebralight, for example. And we have chargers that limit the charging voltage at 4.2 V. So can't we say it is "safe" to use unregulated Liions there?
(Please remember: I'm ONLY talking about lights equipped with one single cell, of course. Using unprotected cells (no matter of primary / rechargeable) in series is a risk and should be avoided in any case!)
At the moment I'm using both, surely only high quality brands. Protected AW3400 and unprotected Panasonic 18650B. Same cells, the unprotected are cheaper and are providing a little bit more capacity.
Of course I'm taking care that they never will catch heat, frost, water or damage. I'm storing them one by one in tough plastic containers, so they are safe from short circuit. And I'm exchanging them after 2 or 3 years.
In theory, when you look at a light like the SC600 L2, the only failure where a protected Liion gives us additional protection is an internal short circuit inside of the flashlight. Caused by an electronic failure, by some kind of misassembly in the factoring process, caused by... whatever.
What do you think?