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

[DBSAR]

@blind-eye

What batteries are you all planning to use for the LT1? Should I go protected/unprotected button top/flat top high drain/normal? Thanks.

I will be using Samsung 35E / 3500mah unprotected button top cells for all the LT1 lanterns.

[sbslider]

@BlueSwordM

There’s a pretty good argument against using protected cells for such an item: the internal protection circuit on the cells themselves draw current, which can make standby runtime of the 18650s suffer.

10uA current draw for a protection circuit (arguably could be more in a cheap cell, but likely not), 3Ahr battery, discharge time is 34 years. YMMV (hope I did my math correctly)

[Costom56]

Please put me on the list for 1
Thanks.

[blind-eye]

Good info. Thanks!

[DBSAR]

@blind-eye

Good info. Thanks!

Are you in the US or Canada? (we have a Canadian supplier offering a discount to all BLF members for the LT1 lantern for these high capacity cells, but not sure what sellers in the US are offering the 35E Samsungs for a good price there.

[leftdisconnected]

@lionheart_2281

@Lothar

…Would a “heart-beat” or “breathing” feature not add value when camping or having the lantern in a room? That way you can easily spot the lantern in the dark if the illuminated button is away from you. Also, it could help you get to the light in the dark, where-as the button will not provide enough light to see. It should be soft enough not to wake you if the light is with you in the tent. Just my 2c

I think TK said it increases the idle drain on the batteries far too much.

Yes, any continuous change or checking requires that the microcontroller be awake and running. A “breathing” mode needs the MCU fully awake, but a “heartbeat” mode could allow sleeping in between on/off switching (heartbeat brightness should be controllable via the on time). We typically want the MCU to stay in Sleep mode whenever the light is not actually “on” in order to reduce power consumption while it sits unused.

As is being discussed at great length :person_facepalming: in another thread which I will not utter here, lights with electronic controls are never truly “off” unless the power is disconnected via the tail or head or a secondary power switch, such as the tail clicky found on the Sofirn C8F.

It is fine to create a new mode where the light does what you have asked, but this mode would add drain to the batteries. It would still be less drain than the existing candlelight mode, but users might be tempted to leave the “breathing” running non-stop and this would drain the cells more rapidly. That is not so horrible if users understand the cost of using such a mode, but here we get into philosophical territory about user expectations .

If I were to add a breathing or heartbeat mode to a light, I would turn the mode off once the battery voltage dropped below nominal (~3.7V per cell) or perhaps below 33% (~3.4V per cell). I would not want to drain anyone’s cells empty just because they left the light “running” in this mode; best to leave some useful capacity for both emergency usage and the possibility of extended storage. This might also let the user know that they should charge the light to restore the breathing/heartbeat.

That logic could not be applied to any mode that most users would define as “on”, of course. Just my thoughts…

[blind-eye]

I’m in the US. I’ll just have to shop around a bit.

[goshdogit]

@blind-eye

I’m in the US. I’ll just have to shop around a bit.

Remember, the LT1 needs button-top batteries. Or you can add solder blobs to the tops of flat-top batteries if you’re confident in your soldering skills.

Be sure to buy batteries from a trusted dealer. Steer clear of Amazon and eBay, and don’t be tempted by off-brand batteries.

ILLUMN is a respected and dependable US-based seller. Calvin from ILLUMN is a BLF member, too.

They currently have 3500 mAh Sanyo NCR18650GA button-tops for $5.99, with free shipping in the US for orders over $50.

Liion Wholesale is another great US-based seller. Their current price for the NCR18650GA is a couple dollars higher.

[DBSAR]

@goshdogit

@blind-eye

I’m in the US. I’ll just have to shop around a bit.

Remember, the LT1 needs button-top batteries. Or you can add solder blobs to the tops of flat-top batteries if you’re confident in your soldering skills.

Be sure to buy batteries from a trusted dealer. Steer clear of Amazon and eBay, and don’t be tempted by off-brand batteries.

ILLUMN is a respected and dependable US-based seller. Calvin from ILLUMN is a BLF member, too.

They currently have 3500 mAh Sanyo NCR18650GA button-tops for $5.99, with free shipping in the US for orders over $50.

Liion Wholesale is another great US-based seller. Their current price for the NCR18650GA is a couple dollars higher.

Great post :+1:
Once the LT1 goes into production & if Sofirn offers an option with good cells-included or not, i may add links for all US customers & Canadian customers looking for genuine HC 18650s. Maybe we can have other members from Europe & other places around the world chime in with their favorite links to places to buy high capacity 18650 cells too. As of now for us Canadian members we have the deal with 18650Canada offering a discount for us buying for the LT1.

[PBNinja]

For anyone in the UK OLight Uk (no affiliation) usually have a decent supply of button tops.

I don’t know if they’re any good or not but here’s the link,

https://www.olightstore.uk/olight-18650-lithium-ion-rechargeable-battery-2600mah.html

[Lothar]

@leftdisconnected

@lionheart_2281

@Lothar

…Would a “heart-beat” or “breathing” feature not add value when camping or having the lantern in a room? That way you can easily spot the lantern in the dark if the illuminated button is away from you. Also, it could help you get to the light in the dark, where-as the button will not provide enough light to see. It should be soft enough not to wake you if the light is with you in the tent. Just my 2c

I think TK said it increases the idle drain on the batteries far too much.

Yes, any continuous change or checking requires that the microcontroller be awake and running. A “breathing” mode needs the MCU fully awake, but a “heartbeat” mode could allow sleeping in between on/off switching (heartbeat brightness should be controllable via the on time). We typically want the MCU to stay in Sleep mode whenever the light is not actually “on” in order to reduce power consumption while it sits unused.

As is being discussed at great length :person_facepalming: in another thread which I will not utter here, lights with electronic controls are never truly “off” unless the power is disconnected via the tail or head or a secondary power switch, such as the tail clicky found on the Sofirn C8F.

It is fine to create a new mode where the light does what you have asked, but this mode would add drain to the batteries. It would still be less drain than the existing candlelight mode, but users might be tempted to leave the “breathing” running non-stop and this would drain the cells more rapidly. That is not so horrible if users understand the cost of using such a mode, but here we get into philosophical territory about user expectations .

If I were to add a breathing or heartbeat mode to a light, I would turn the mode off once the battery voltage dropped below nominal (~3.7V per cell) or perhaps below 33% (~3.4V per cell). I would not want to drain anyone’s cells empty just because they left the light “running” in this mode; best to leave some useful capacity for both emergency usage and the possibility of extended storage. This might also let the user know that they should charge the light to restore the breathing/heartbeat.

That logic could not be applied to any mode that most users would define as “on”, of course. Just my thoughts…

Yeah the heartbeat should be a hidden mode like blinkies, and not a standard feature when the light is turned off. I would think that the heartbeat would conform to the same low battery protection as all the other modes.

[Nev]

@PBNinja

For anyone in the UK OLight Uk (no affiliation) usually have a decent supply of button tops.

I don’t know if they’re any good or not but here’s the link,

https://www.olightstore.uk/olight-18650-lithium-ion-rechargeable-battery-2600mah.html

Or these

Fogstar Batteries | The UK’s #1 18650 Battery Retailer

Nu Battery - The UK’s Best 18650 Battery Retailer

[f0xx]

@leftdisconnected

If I were to add a breathing or heartbeat mode to a light, I would turn the mode off once the battery voltage dropped below nominal (~3.7V per cell) or perhaps below 33% (~3.4V per cell). I would not want to drain anyone’s cells empty just because they left the light “running” in this mode; best to leave some useful capacity for both emergency usage and the possibility of extended storage. This might also let the user know that they should charge the light to restore the breathing/heartbeat.

That logic could not be applied to any mode that most users would define as “on”, of course. Just my thoughts…

I think this is probably the best way to add a feature like this. I think few would complain if it wasn’t the default, and having the option would satisfy those who would use it. Having logic to reserve some amount of battery seems wise as well.

I don’t remember where, but I think I read that leaving the button LED on at a low level used less power than engaging the MCU to do stuff like this despite having the LED on for less time.

[teacher]

One thing for sure , it won’t be on the soon to be released LT1 anyway.

So there should be plenty of time to discuss it.

[Madtoffel]

Maybe we can have other members from Europe & other places around the world chime in with their favorite links to places to buy high capacity 18650 cells too.

NKON (https://eu.nkon.nl/ ) has been a cheap and reliable source for batteries in Europe for years.

Inside Germany the TLF has an ongoing cooperation with Akkuteile.de with special discounts for TLF members.

[MascaratumB]

@Madtoffel

Maybe we can have other members from Europe & other places around the world chime in with their favorite links to places to buy high capacity 18650 cells too.

NKON (https://eu.nkon.nl/ ) has been a cheap an reliable source for batteries in Europe for years.

Unfortunately, for those living abroad (meaning, outside NL) the shipping costs almost kill the deals on the batteries :zipper_mouth_face:

[f0xx]

@teacher

One thing for sure , it won’t be on the soon to be released LT1 anyway.

So there should be plenty of time to discuss it.

Good point! Maybe we should start a new thread (or find an appropriate one that already exists) for that discussion. Since it is all firmware, it could be added at some point to the LT1, but it isn’t explicitly LT1 related.

I’m always up for a good discussion, as long as the end goal is improvement and learning, not just senseless bashing of the local heroes.

[f0xx]

@goshdogit

@blind-eye

I’m in the US. I’ll just have to shop around a bit.

Remember, the LT1 needs button-top batteries. Or you can add solder blobs to the tops of flat-top batteries if you’re confident in your soldering skills.

Be sure to buy batteries from a trusted dealer. Steer clear of Amazon and eBay, and don’t be tempted by off-brand batteries.

ILLUMN is a respected and dependable US-based seller. Calvin from ILLUMN is a BLF member, too.

They currently have 3500 mAh Sanyo NCR18650GA button-tops for $5.99, with free shipping in the US for orders over $50.

Liion Wholesale is another great US-based seller. Their current price for the NCR18650GA is a couple dollars higher.

I’ve had good experiences with both of these sellers (Illumn and Liionwholesale). Got what I ordered at a good price, and it shipped out quickly. I’ve seen a bit from Calvin on the forums, and he seems a stand up guy to do business with.

[Madtoffel]

@MascaratumB

Unfortunately, for those living abroad (meaning, outside NL) the shipping costs almost kill the deals on the batteries :zipper_mouth_face:

That depends on where in Europe you live, I guess. Yes thier shipping costs are quite high but delivery to Germany costs 6,50€ (2,50€ when you are okay with waiting weeks) which is worth it, when you are buying a bunch of batteries or buing them together with a flashlight.

[MascaratumB]

@Madtoffel

@MascaratumB

Unfortunately, for those living abroad (meaning, outside NL) the shipping costs almost kill the deals on the batteries :zipper_mouth_face:

That depends on where in Europe you live, I guess. Yes thier shipping costs are quite high but delivery to Germany costs 6,50€ (2,50€ when you are okay with waiting weeks) which is worth it, when you are buying a bunch of batteries or buing them together with a flashlight.

I bought from them once, and the shipping costed me more than the batteries :zipper_mouth_face: 13€ for the bateries, 14€ for shipping.
Buying some more batteries may be worthy, but with those 14€ I can get some more batteries from China, from “reliable” stores.

BTW, in Germany you also have this one:
https://www.outdoormesser.de/epages/62013711.sf/en_GB/?ObjectPath=/Shops/62013711/Categories/Lampen\_*Co/Batterien*\_Akkus/Batterien

Just bought an Acebeam light from there and shipping was faster and cheaper than from NKON! They have a small rang of offer, though :confounded: