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

I think we are looking for a recommendation for a 5000K Osram LED as well, chime in if you have a recommendation.

Please add to interested list x1

With CRI over 95 and R9 over 95 it should be an excellent lantern. Much better than the Samsung.

When I light up my Nichias everyone notices the excellent colour. But with a lantern it will be a lot better because it will be used as general lighting in a room or outdoors, and for extended periods of time.

If the Squares will make it into the lantern you should remind Sofirn of the 3030 footprint, to have a correct ledboard made.

good point.

Just out of curiosityā€¦ Is the center bolt going to be copper sleeved to transfer heat to the batteries when used in the winter?

Red light?

Sorry donā€™t feel like backreading 111 pages

no and no, and I donā€™t blame you.

ALL batteries will perform poorly in cold weather, regardless of whether they are lithium, Alkaline, Zinc or lead-acid. In fact, a lithium battery will still outperform a comparably-sized Alkaline or lead-acid when the temperature drops. As a result the battery will warm up internally and gain enough ā€œjuiceā€ to run when loaded. I have had a 18650 light stored in the center console of my truck now for the last 4 years, and even during ā€“30 Celsius winters it worked fine. Its not a big enough concern to have a heater-tube for the cells, as 80% + will use the lantern in summer, indoors, or at least stored indoors in warm temps.

Agree that also reduce the temperature of LED/head section.

One thing though:

NEVER CHARGE LITHIUM ION CELLS (18650s/21700s/14500s/18350s) below 0C.

Otherwise, they will degrade permanently.

I forgot to mention that charging cold LiIon cells is bad for them. (meaning any heat tube wont work if the lantern has been off & stored in a cold area with low batteries.

Yeah forgot too honestly about what Lexel implemented in the form of a temperature charging cutoff at 0C.

Storing (or using) LiIon cells in cold temps is fine, its just they donā€™t like to be charged when really cold. (I would warm them up to room temperature first before charging them.

Iā€™m interested in one as well
Thanks!

Looks very sweet! Please add me to the interest list.

If this ever happensā€¦ I am interested!

Please add to interested list x1

I added to the charging circuit as described in the datasheet a NTC and 2 resistors to set low and high temperature
as the prototypes get build by Sofirn this needs to be tested as well

Iā€™m interested in two
Thanks

Iā€™m interested in one piece.
Thank you for your great job.