I guess I can get Keeppower and XTAR protected cells from the place where I normally order cells from, but they're literally twice as expensive as a Samsung 35E cell... that's a hefty price tag for a tiny PCB with probabably just a tiny IC and a mosfet on it :/
I’ve no experience with XTAR protected cells, but I’ve found that Keeppower cells tend to be a bit too wide - several of my lights won’t accept them.
I’ve had good results with Eagtac cells - the 3500mAh cells are rated for 10A, with a protection circuit to match, and they worked well in the BLF A6 I used to EDC.
Be warned, though - my Eagtac cells are the old model with the protection circuit at the negative pole. I haven’t tried the new version with the protection circuit at the positive pole yet.
thanks for your review of this light, valuable experiences for everyone.
most of my lights are Convoy, never looked at this model
Found this review on banggood... I don't understand why anyone who actually bothers to measure the cut off voltage would still give 5 stars, even though they clearly found their LVP not working.
There may be a chance the review was modified.
Why would he given 3 stars in the written review then?
Banggood are known for modifying or even deleting “less favourable” reviews.
What? No way. Get out. That’d be downright dishonest.
Next thing, you’ll be accusing them of luring people in with promises of free gifts, and never delivering.
I think I’ve heard that about banggood before, and even though I condemn that behavior, I still chose to order from them and haven’t had issues with them so far. That being said, my 3-star review on the S9 (and it only got that because I rated it 5/5 for appearance I guess) is still “processing”. Also still waiting for the promised refund, but I expected that to take a few days anyway. Got my refund now.
Simon from Convoy replied to me on aliexpress and said “It [the new driver] has cut off normally .” and also sent me a tracking number. Not sure what normal means in this case, because if it’s just designed like that… eh, guess we’ll see. Will report back once that has arrived and I got a chance to test it.
OT: Frankly I’m not quite sure about the dangers of a charger that doesn’t cleanly cut off… I suppose if lithium-ion batteries get overcharged, it’ll cause an irreversible chemical reaction (plating), but no idea if the battery will even just accept any current (apart from what’s lost due to self-discharge) when held at the end-of-charge voltage like that. Does anyone have a good resource that explains how bad it actually is for the batteries?
Alright, here's an update on the replacement driver Simon from Convoy sent me free of charge:
He sent two drivers, both look physically undamaged, and both behave exactly the same way as the one in my S9 did. This tells me that the bad LVP is either baked into the design (aka just bad design), or that a whole batch of drivers have a manufacturing defect (such as a different resistor value in a voltage divider or something). They also both charge a bit high (4.25 and 4.26 V). But hey, at least they're consistent I guess.
I'll get back to Simon on aliexpress later tonight, will see what he says. I'll also have a closer look at the driver later to see if maybe I can replace a resistor to make the LVP function properly.