*BLF LT1 Lantern Project) (updated Nov,17,2020)

Please count me in for one. Thanks!

I think leftdisconnected is correct about the protected cells not being a safeguard.

Regarding the prior question, I don’t know the TP5100’s algorithm, but a typical lithium ion charge function would transition from constant current to constant voltage charging once the charge voltage (which is higher than the rest voltage) reaches 4.2V.

At that point, the current the battery draws from the charger starts to slowly decline. Once it falls below the threshold, the charger terminates, and does not restart until either the battery is removed and reinserted, or the voltage falls below an initiate threshold. One datasheet I found for the TP5100 (mostly in Chinese), seems to indicate the termination current is 80mA, and the restart voltage is 0.080V below the charge voltage.

As you speculate, that would mean the LED’s drawing continuous power would cause the charger to stay on indefinitely if left plugged in with the LED’s on. However, the charge current absorbed by the batteries should slowly decline, asymptotically towards 0.

It would likely accelerate battery capacity loss, but I wouldn’t expect it to actually overcharge the cells and create a hazard, as the voltage should stay at 4.2V.

I could probably test that using a single cell, (one that is well used i have) by connecting the USB charger, turn the lantern on with the cell connected to the lantern as it would normally be, but with a volt & amp meter connected to the cell to see what happen on the meters over time while the lantern is running when the cell reaches its full 4.2 volt charge, (say with the lantern running on a medium mode setting.

Honestly, this lantern sounds like it will be really helpful in nations that have limited electricity, where there are sometimes daily brownouts and blackouts. If I could afford to, I would buy one (plus batteries) for each of my family’s households that are overseas.

Great point! I guess we sometimes forget the luxury a lot of us live in. Thanks for reminder I should be much more grateful.

That’s most excellent TK! Thanks!
This lantern is breaking new ground in so many ways! :+1:

Interested for 2

I’m in on 1!

First BLF group buy, already psyched! :smiley:

Friends and family need these, I’ll get some V2 too, it’s only money.


BLF’s mantra :stuck_out_tongue:

Just bumping up here quickly, after some time AFK. Is the V2 a real thing, or still a fantasy?

Please add me for 1 more lantern for a total of 2.

Thank you!

I was curious, so I dumped the list in Excel to get a count.

It looks like somebody who is generous and wants his friends and family to have the best.

The runner up is on the list for 8 and wants his pals to be well illuminated in deep, dark, Baja Mexico.

Right now, it’s what we call “vaporware”. It’s a product that is announced but yet to be made. DBSAR has indicated that work on V2 will not commence until after V1 is finished and available for sale. Then again, a lot of the work that went into V1 will obviously carry over to V2. :wink:

The future V2 or “LT2” will be a more expensive deluxe version, with all the goodies & design of this LT1, but with some added features, as in adding a power-bank feature, possible wireless remote control, built in dawn/dusk timer, motion-on/off sensor, and maybe even an alarm clock. and other classified additions. :sunglasses:

can opener?

Cuddly toy ?

bun warmer?

Sound card and speakers that makes a roaring noise like a gas lantern?

Ah, this takes me back to childhood, when I’d want some toy and my parents would assure me twe should wait because there would soon be something better that I’d want more.