Sorry for the newbie question, but should I leave unprotected cells in my lights when they are not in use? Is there a safety concern? Again, apologies for the naive question.
It depends on the specific light. Some lights have very low parasitic drain and some don’t. If you aren’t going to be using a light for at least a few days then it’s best to mechanically lock it out. The SP70 has the tail switch to cut power. Some lights with anodized threads allow you to turn the tail cap half a turn to cut power. Lights with raw threads might require taking the battery out.
Some lights may take a couple of years to drain the batteries while other lights may only take a couple of weeks.
I lock out most of my lights mechanically. The ones I don’t are used pretty often and have very low drain. They also use protected cells.
All my lights using unprotected cells get locked out.
My SP70 (kit version) has arrived 2 days ago. I’m very satisfied with it. I didn’t find any imperfections on the body/anodization nor in the reflector. It seems Sofirn made big progress in dust-free assembly. Those 26650 cells included in the kit version (from Amazon DE) seem to be their standard 26650s with 5.500mAh and without “High Drain” label.
There is nothing wrong with the SP70 Kit. In fact, it checks all the marks for me. Tail switch w/momentary, check. Super bright, check. Good batteries, check. Wide hot spot, check. Weighty for thug beatings, check. Tint, it has one, check. All kidding aside, I am anxious for the BLF version because it is sure to kick ass. I’m just wondering what the consensus will be on the specs and how we will resolve the range of priorities. AR glass, fancy springs, perfect button alignment, etc.
I now like my Sofirn SP70 more than ever. What happened was I noticed a voltage inequality between the 2 EBL 26650 cells after using to where they needed recharge. I correctly attributed this to the lack of good contact between cells, due to Flat tops. I drove to Home Depot and purchased a pack of Neodymium Disc Magnets (pictured). The foam adhesive removed easily, and the bare magnet fit the Flat top well. Now I can feel both cells are equally drained and the runtime has dramatically and to my great delight increased as one expects and hopes of 2x26650 5000 mAh rechargeable lithium ion batteries. Perfection achieved on a strict budget!
Wow big, hefty light. Just what I was looking for - but won’t turn on. DOA it seems. Green Shockli 26650s worked just fine in D4S. Topped them off to 4.2 last night. Connections cleaned, head and tail as tight as I can get them. Bummer.
First light I have gotten where it won’t turn on right out of the box (well, after the cells are in anyhow).
Guess I will be pushing back to Amazon in the morning.
I think the magnet material itself is not a good electrical conductor and most of the current might be passing through the thin plating on the surface of each magnet (probably nickel plating). For flat top batteries I would cut a small round piece of copper (copper plate 2mm thick from Lowes) and solder it on top.
Sorry to hear about the DOA. Did the green LED light up the side switch? I assume the connection between each battery in series is good. If you have a few 18650 button top batteries, maybe you can use the plastic tube adapters and try those batteries?