Huh? I didn't know there was an OSH project one.
-Garry
whoops :weary: my bad, apparently there isn’t one, they are all AA holders.
I just assumed that there is one for 18650 since there are plenty lights that use them…
Sorry.
Is there any downside to using protected cells in this case, other than cost? Couldn’t the redundant protection be a good thing? (I always use two condoms ;-)) I’m thinking 3400 Mah Panasonics with the PCBs.
It will additionaly lower the output voltage. Now if you are using the light with buck driver for one led only this won't be a problem, but if you are using unregulated driver and 2 leds light would start dimming sooner than without protection. If you have more leds than 2, then driver should be boost and should work harder if it gets lower input.
Compare battery curves with and without protection at HKJs page to get the impression.
In short: protection is adding some resistance and lower output voltage resulting sooner reaching Vf of the leds. Double protection is good, but it means you have add some looses to the circuit and you get lower efficiency. Of course the amounts are rathrer small, but can count in some cases. So it depends......
The Pannovo battery case that I have - which is the same as the SolarStorm BC-01 - either limits its current output or has a large resistance somewhere that lowers its output.
When testing my modified X6 bike light, its is beaten by an ordinary bike 2S2P battery pack which has 4 pcs 1015 mAh 18650s (based on BT-C3100 tests) no matter what cells I used: be it 4 pcs Panasonic 3400 mAh NCR18650Bs, 4 pcs Sanyo 2600 mAh UR18650FMs, or 4 pcs Samsung 2900 mAh INR18650-29Es, all fully charged. The ordinary 2S2P low mAh pack can last for more than an hour before the X6 (fan cooled) turns to low, while the Pannovo case lasts 5 minutes at most.
When using my stock SingFire SF-90, however, The Pannovo case with high quality cells lasts way much longer than ordinary 2S2P packs.
Nightbird95, it is the springs in those cases that causing the high resistance, AFAIK. Hi resistance shows up when you try to use high current. With X6 you use about 5A on high while with SingFire SF-90 somewhere around 1A (guessing). If you would measure voltage at battery and driver terminals at the same time you would notice big voltage drop with higher cuurents (ie. higher modes at X6). At X6 voltage drop is so high the driver thinks battery is exhousted.
I've learnt something lately about those problems. You can also see the thread where Garry tries to improve current over his driver or latest posts about DX driver you are using in X6.
Edit: In addition to that there is problem with connector resistance. It is problem with all connectors of that type. No big deal while you run at low currents, but with higher ones over 2A resistance become very limiting factor. See thread at DX forum.
A question from a newbie: How would a Yinding or a Yinding clone do if paired with this Solarstorm/Panovo battery pack filled with protected cells?
Thanks ledoman! 
Since they are pulling less or around 2A I would suspect they would run just fine. Protected batteries are longer so the springs in the case would be more tight resulting in less resistance. This might compensate the resistance of the battery protection boards.
Also when runnig two leds in series using higher curve cells like Sanyo is better than Panasonic in terms of voltage staying above Vf - ie. full brightness. Of course Panasonic would run longer but less bright in the last third of running time since drivers are not regulated, AFAIK. But this you probably won't note until very end, since the eyes can somewhat compensate the amount of light. It is same effect as Aperture with cameras.
A user over at MTBR has confirmed that long protected cells fit in this new battery box. He also warned that battery orientation is different compared to the old Pannova case.
-Garry
Got one battery case from the Gearbest. On the first sight it is smaller and lighter than the old one. The batteries are inserted differently, but the orientation is clearly marked. The cover is rectangular not square so it can be inserted only in two way ie. rotating 180 degrees. If cells are inserted properly there is no way to make a short.
I've tested overcharging cut off and it kicks in somewhere at 8.46V. So if the charger fails to stop charging protection circuit would cut it off. Big improvement over the old one.
Tried to charge my phone and it works, but haven't measure anything yet.
What I dislike and proved with HKJ is lack of cross connection between battery pairs at the bottom of case. The old one had cross connection on the spring side. This new one doesn't have that feature anymore. This means batteries would not help each other in all possible paths current is flowing. With cross connection battery pack works more like one big 8.4V cell while in the new version pack works more like two 8.4V parallel cells.
Thanks ledoman, but what does the low voltage cutoff trip at? Is it 5.0v as listed in the specs? And how big of a deal is the lack of cross connection? Is that something we can easily add (or not easy due to those springs being so deep down inside)?
My recent Ebay order of the original Pannova cases was refunded due to no tracking updates (I can't fault the seller as they were very courteous and offered the refund even though I was just inquiring and willing to wait a little longer).
I'm going to order (2) of these new cases.
-Garry
Garry, haven't test the low voltage cutoff yet. To me is more important overcharging cutoff so I've tested that first. Shurely will do the other too.
If you have quality cells and you balance them from time to time not having cross connection is not that much of an issue. It is just the load is not so evenly distributed. With this new one the springs are on the top side. On the bottom are just two pairs of buttons. Will try to provide picture of it. Making cross connection would be hard as there's plastic wall between the pairs of buttons.
—Are there any advantages or disadvantages of charging the cells while in the case or removing them and charging them in an external charger? I have an Ultrafire WF-139 with an output of 4.2V/450mA . I use a Dinotte 7.2 volt Li-Ion Smart charger for charging In the case. Output is 9V/1.5A.
Tmax, it also depends on quality of cells you are using. In general I would say charging in the case is more practical. Since the new one has overcharging protection it is also safe enough. Your charger has a bit high output voltage! It should be 8.4V +/- 0.05V.
Ocasionaly it is good to charge cells separately in a good charger for balancing purposes so the all cells get equal voltage. If your cells get charged in Ultrafire WF-139 every time to the same voltage it good to use it few times a year.
Bad news, at least with mine sample. Overdischarge protection kicks in at 4.65V and stays off until voltage raises over 6V. No cell that I know won't raise it's voltage from depleted 2.3V back up to 3.0V under no load. Protection stays on until you change the cells and the capacitor inside gets almost empty which happens in about 10 seconds.
Overdischarge protection should kick in at 5.0V by specifications but I would rather see it at 5.5V. I have another battery case comming from Kaidomain and I'll see if the other one is any better in this regard.
Forgot to tell how I tested it. I've taken stepdown voltage regulator, connected it's output to the battery case springs and put DMM in parallel. Then I've changed voltage up and down to catch those figures.
Oh boy! So it sounds like it's just a 2S2P case to use like the old Pannova (which had no protection), no reliable protection. Thanks for testing.
-Garry
No Garry, it has perfect ovecharge protection at 8.46V which is way more important protecting you from bad chargers and possible damage (explosion, flame, venting, ...). The overdischarge is minor issue as you have red led warning on your light and with some lights you would see considerable dimming so you would know it. Overdischarging means only lost of capacity to the cells, no other harm.
This box is much better in regards above than it was the old one. Meanwhile I've checked USB output voltage and it's tad on 5.02V. Very good!
True. I likely wouldn't ever charge individual cells in this case though, so the over-discharge protection is more important to me. Can you quick check at what voltages those led battery status indicators change? Does the last one flash or just go out when you reach the low voltage cut-off?
-Garry
I've already cleaned out my desk (floor actualy ;-) ). Won't have time tomorrow. Will keep in mind to do it....