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

Sorry, but you need button top cells.

Oops, misunderstood it or misread it :zipper_mouth_face:
Thanks for clarifying BlueSwordM :wink:

Not I can spend my money in a informed way :smiley: :money_mouth_face:
I’ll be a good buyer :innocent:

Please add 2 more for me.

Thank you.

I’ve been waffling about if I want a second one or not… Why the heck not.

Put me down for a second one.

#463 in the list.

Okay, so it sounds like just to be on the safe side, it would be a good idea to stick with protected cells (and maybe just charge with an external charger if I want to charge while the lamp is running — I’ve got a USB 18650 charger so that’s not a big deal).

Protected cells wouldn’t do anything at all in this case.

It’s not actually dangerous. Just bad for cycle life for the cells.

Unprotected vs protected does not matter at all.

Bad for cycle life due to the low drain? I planned to use four protected 2600mAh 26F’s and some unprotected 30Q’s, but not together of course. Is that a bad idea?

If as suspected the internal charger keeps charging the cells forever when the lantern is on, running off USB, the cells protection circuit would be a safeguard?

Will the upgraded (V2) version of the lantern begin development when the V1 lanterns finish shipping or have both versions been developed side to side?

As i do not know if the TP5100 charger chip would actually do that, i think either Toykeeper or Lexel would be more qualified & knowledgeable in that category than i am.

The lantern running without batteries, off a USB power source, opens up quite a few options i was not aware of! It could even be turned into a home appliance… The battery tube could also be replaced by any thread compatible foot design you want. Adding remote control should not be too complicated either (at least on/off)… This LT1 project is exceeding initial expectations in many ways! :+1:

I have ran it for hours during testing just plugged into one of the USB power ports in my RV trailer using a 10 foot long USB-C cable with no batteries in the lantern, proving the LT1 can be a multi-powered by almost any 5 volt power source that can supply at least 1.5 amps.

It’s bad for the cycle life of any Li-Ion cell to keep it charged at 100% and even worse to keep charging it once it has passed 100% charge capacity. For “float” charging set-ups, you are better off using lead acid batteries. Perhaps, if the terminal voltage of the charger were set below the max charge voltage of the Li-Ion cell, some of its life can be spared. But I don’t know that. I’m just guessing it might be possible. Best is to not overcharge, not over-discharge and not overheat the cell ever.

Just for grins I ran some stats to see what the breakdown of lantern interest are as of this minute:

1,221 users have signed up for a total of 1,848 lanterns as follows:

  • 1 lantern - 801
  • 2 lanterns - 297
  • 3 lanterns - 74
  • 4 lanterns - 33
  • 5 lanterns - 7
  • 6 lanterns - 4
  • 7 lanterns - 2
  • 8 lanterns - 2
  • 10 lanterns - 1

Still time to get your addition lanterns on the list :slight_smile:

I’m on the list for one. I’ve long been “interested” in more, but my wallet disagrees, so I stay at one. If I come up with some more money, I’ll certainly be looking to add a couple more lanterns for gifting. :money_mouth_face:

Please add me to list to purchase one

I don’t know if I missed it or not, but will the USB port on the lantern work with USB PD? Most lights that I’ve heard about, or have experience with, that use a type C port won’t charge with PD, you must use an A to C cable.

yes, it will likely work with the USB power delivery (PB) type chargers. the TP5100 charging chip can accept and regulate any input from most power sources i have tested.

It appears that protected cells use IC’s like this one, which provides over-discharge, over-current, and over-charge protection.

However, the over-charge cut-off is triggered at a specific voltage. Thus, the protection circuit will only shut off current after the voltage reaches that trigger, which it may never do if the over-charge trigger is above the output voltage of the LT1 charging board.

It seems likely that the cells would just sit and “soak” at ~4.2V for as long as the light were kept running. Cell charging current would drop quite low and nothing dangerous would happen, but li-ions are not meant to remain in constant-voltage mode indefinitely, which is effectively what happens with the light running and the cells charging at the same time.

So, the answer is probably that protected cells will not be a safeguard.

Please correct me if I’m wrong here as I don’t want to misinform anyone.

My collegue wants one. I’m in for one atm, please add one for a total of 2 :slight_smile: