Those are both good choices. Protection is likely not required for this application, as the LT1 has low voltage protection. If you install the batteries properly, you can’t really draw anywhere near their rated current, so over current protection doesn’t come into play either. But it doesn’t hurt in the LT1 to have the protection either.
The Keeppower says 1A charge current, you will be well below that if you have 4 in the LT1. Discharge is not a problem. The Sanyos have a higher rated charge current, so again no problem. Either will work very well in the LT1.
I can’t tell you exactly what sorts of protection the different cells you listed provide, but typically it will disconnect the battery from the load if you try to draw too much current, and will do the same when the battery voltage drops below some threshold, generally around 3V or maybe a bit lower. Illumn says the sanyo cuts of at currents around 20A, I didn’t look up the voltage threshold for low voltage protection. The Keeppower website says,
Protected cells can still be a good idea, especially if you intend to gift the light to a non-flashaholic who isn’t familiar with cylindrical Li-ion cells. There shouldn’t be any reason to remove the cells once installed if you are using the built-in charging, but if one cell is inserted upside down it will short to the other cells thanks to the ring contact design.
That said, if you intend to insert the cells once and never remove them, protected cells wouldn’t be worth the extra cost in this light.
Thanks MtnDon, sbslider, and Rayoui for the info, yes it certainly does help.
Sounds like the protected cells reduce the capacity or something.
The reason I want to have the protected cells is so they can be used in high output flashlight applications also if needed.
I would like to have the higher button top ones, that’s why I was looking at the Keeppowers.
I thought that the built in charger uses 5v 2a charging adapter, I am guessing that you mean divided by the 4 batteries that would still be under the 1A charge rating of the Keeppower batteries.
If the Panasonic protected ones have the same level of protection as those keeppowers have I would just go that route.
The Mountain Electronics webstore is showing the picture of the EVVA batteries on their listing for the Sanyo/Panasonic NCR18650GA Protected 3500mAh. Anyone know if the pictures are incorrect, or are the EVVA batteries Panasonic?
A protected cell should have the same capacity as its unprotected counterpart. The difference is that the protected cell is slightly longer, slightly fatter and costs more. The max current is determined by the protection circuitry and is almost always less than the bare cell itself, though high current protected cells do exist.
If you intend to buy protected cells for using in high current lights, make sure the light isn’t going to pull more current than the protection circuitry is rated for. Otherwise the protection will trip immediately and the light will turn off. That shouldn’t be an issue with the LT1.
Can someone more knowledgeable and eloquent than myself speak to the importance of keeping a married set of cells? Is it less crucial to do so for the LT1?
If you use four 3500mAh cells, the total capacity will be 14000mAh.
You can use cells of different brands, sizes, capacities and ages. Just be sure the voltages are matched when inserting them. If they are too far off, the cells could get quite hot as they equalize.
I agree with Rayoui. I’ve run several different sets of cells in my LT1. Just have all 4 at the same voltage, or close to it, when you install them. If you don’t have a meter the easiest way to do that is charge them in another charger first.
I would think it best to keep the capacities the same or very close. If the capacities were too different (2600 with 3400 for example) when the 2600 gets low would that not start a transfer from the higher level cells to the lower level. I doubt anything seriously bad would happen as it would be a slow process over time. You would be wasting some energy transferring it here and there.
But then my personality is such that I am bothered my un-matched sets of anything.
The only problem would be with a high amp consumption where unbalanced IR might lead to some unbalance under load resulting in current transfer when decreasing the load.
Very little transfer risk with the 4 batts in LT1, because the current drawn is low each batt gives what it can and the capacities are summed.
That beeing said i am the kind of "match-it" person too ;)
agreed, if you can, then you might as well keeped fairly matched capacities. But if you are scrounging for batteries the LT1 is not going to cause problems for the batteries.
I’ve been using mine for a week now, and tried charging it for the first time today. But when I plugged in the USB cable, the switch light stayed orange. So I unscrewed the head a bit (a few millimeters were enough), and the green light came on. At that point I performed a battery check, and the lantern was giving me random results between 4.1V and 4.4V, all in the same sequence. So I decided that I wasn’t able to trust the charging mechanism before finding out more about this behaviour, and now I’m charging the batteries in my Opus charger. All batteries were at 3.70V when I removed them.
I’ve not been able to keep up to date with this thread, so I’m not sure if this issue has been mentioned before, and whether it’s a problem or whether I can ignore it and still safely charge my batteries in the lantern?
When you unscrewed the head the batteries were disconnected from the LT so the light turns green since the LT is being powered from the charger. This is the normal behavior when the batteries are not powering the LT. The difference in color when charging and not charging is really not noticeable unless you are looking closely at the LED when plugging in the cable. Try plugging and unplugging the cable with the batteries connected and see if it changes color.
A battery check with the batteries disconnected really doesn’t tell you much of course.
You are totally correct, just checked and could see the two red ‘wedges’ appearing on the left and right of the orange backlight. Thank you very much, I’m out of panic mode now!
Generally, Lixx cells connected in parallel behave like communicating vessels.
Their capacity and IR do not matter as long as no cell is overloaded.
So, you can mix any cells of different IR, as long as each individual cell would not be overloaded if used alone.
As it was mentioned before, the cells should be fairly equal in voltage when paralleling the for the first time, with less the 0.1V difference preferrably.
I noticed that the red led’s on my first one (batch 1) are a brighter red, making it easier to discern the color. The second has a noticeably less bright red, meaning one has to look with more care.
Received my LT1 from the 11/11 sale today, seems to work fine, except 1 of the cool LED’s doesn’t work. Good thing I like warmer light!
Will try & contact Sofirn after Xmas to look for a resolution
Received my 2nd LT1 today, this one is a gift for my son. Won’t get to give it to him until early January, so I have a bit of time to check it out.
First impressions of changes from batch 1:
-The bail handle lines up with the switch, and it moves to either side equally. It “catches”, or rubs slightly on the top in the fully recessed position equally on either side.
-Same incorrect manual, or does the LT1 really put out 5600 lumens? Maybe 560?
-The connection of the bridges for 4 and 5 were obviously done by hand, and could use maybe a bit of clean up to remove flux. But 6 and 7 were not at all soldered, so if/when someone goes to solder them (I would just use pencil lead personally) they will have a bit less chance of damaging them as one person reported fairly recently.
-same rev 4.3 driver board, pot is there. I won’t remove it, as it won’t get in the way of the cells I have installed in the LT1.
-the switch cover doesn’t have the Thorfire “T” on it
-the orange LED is brighter on high than my LT1. I thought mine was broken for a bit, but shadowing the switch I can see that the batch 2 LED is just brighter. I may compare current draw at some point just to see if its much higher. I can see how FlyingLuminosity got tricked into thinking the red LED was not on, as with the orange LED on high, it’s not easy to see.
-the wires seemed to be better organized. a couple of twists of the driver board and its easy to see where all the wires go. On my LT1 (which I have had the driver board off seeveral times) I couldn’t ever really see clearly which wires went where. I didn’t try hard, but my sons seems much better organized.
I flashed the most recent FW, cleaned the flux residue, now I’m charging the batteries just to see if the battery voltage comes out a bit below 4.2 like DBSAR reported. I still haven’t tested mine, some day. The batteries in my sons are nearly charged anyway, so I figured it won’t take too long to check out. Edit: fully charged batteries measure 4.16V, perfect.
Edit: Contrary to what MtnDon reported, the red charging LEDs on my batch 1 and 2 LT1s look identical.
