I have a Sony BCG-34HLD charger that works ok, but I was interested in a charger that could “read” NiMH battery stats, refresh and discharge them, and also let me choose charging rates.
I found some models with good prices ordering from China, but I always find some info about them that I dislike, or they are not totally reliable.
The Opus BT-C700 seems to be the best regarded NiMH charger overall, but I’ve noticed that it does trickle charging after the battery is done with.
Since I only use LSD NiMH, I don’t see why I would want this feature. I want charging to be completely cut after the battery achieves full status. Even if the harm is minimal, I would rather find a model that does not do unrequired actions to my batteries.
The other models I read about usually had problems like lack of precision when reading battery stats, or sometimes they would overcharge a battery. I was hoping to get something that is pretty reliable and treat my batteries well, or I might as well stay using what I have. This Sony charger is supposed to cut charging completely after it is done with the battery, but it doesn’t work correctly if the battery is not almost empty. I tried the other day with a chinese NiMH that was at 1.3v and it kept charging to 1.44v, batteries were pretty hot. I use a multimeter since this charger lacks any display. But when I tried it with the batteries empty it would charge them very quickly (since they are only 1300 mAh) and would not stay lit for 7 hours (it is supposed to cut off all charging after 7 hours, so at 360mAh charging rate it is supposed to deal with a 2500mAh as maximum capacity). The manual of this charger claims it will always stay lit for 7 hours so I would think that it does have a voltage meter and it would trickle charge lower capacity cells until the 7 hours have passed, after they were charged. But in reality I guess it turns off completely after the voltage meter figures out the battery is done with, but it won’t work well if the battery was not empty, I guess.
That is why I wanted to try a smarter charger with more features so I can more reliably prepare cells to be good to go and not botter if I left them in the charger for more hours as I should have, or if they were half-full and I wanted to complete their charging.
So, is there a better charger than this Opus for my needs or should I accept trickle charging? I looked at some hybrid models that would also work with Li-ion, but I don’t really want to deal with Li-ion right now so I would prefer something specific for NiMH. I understand Li-ion has a lot more capacity which is great for flashlights, but LSD NiMH is safer, will last years with decent charge in them and don’t get as hot, no risk of fire, and they are also lighter and probably better for trekking around and camping at national parks.