I use a SF 9AN for work, and carry a couple spares in my bag. The bag sits in the car, so the batteries are subjected to various temperatures.
I normally use the same battery and recharge it as needed. This battery was bought in '05, is marked CM17, has many recharge cycles on it, but it still works fine. The spares stay in the bag unless I need them. I occasionally take them out and throw them in the charger. They were both purchased in '06, are marked CP26, and have very few recharges on them. I store them in my bag with the plastic cap on the positive side, and nothing metal touches either end.
When I charge the batteries I use a SF charger, wait until I get the flashing green, remove them, and put them back in the charger until I get the flashing green for the second time. I read somewhere on this forum that this was the correct method.
Lately I've noticed, that whenever I pull the spares out, one or both of them are completely discharged. Can't remember the last time I charged them, but I'll guess it was one or two months ago. This is a reoccuring theme. Luckily I have a SF M2 as a backup light.
So is this normal? I thought that cold weather can drain batteries, but it has been very hot lately. Does heat have the same effect on batteries?
How long should I expect these batteries to hold charge, when sitting unused? Do extreme temps make a big difference? Do I have a bad batch of batteries?
While we're on the topic, how many recharge cycles should I expect to get out of a B90? And are there any good B90 replacement batteries out there?
*edited to add: My SF charger is marked CN400.
I normally use the same battery and recharge it as needed. This battery was bought in '05, is marked CM17, has many recharge cycles on it, but it still works fine. The spares stay in the bag unless I need them. I occasionally take them out and throw them in the charger. They were both purchased in '06, are marked CP26, and have very few recharges on them. I store them in my bag with the plastic cap on the positive side, and nothing metal touches either end.
When I charge the batteries I use a SF charger, wait until I get the flashing green, remove them, and put them back in the charger until I get the flashing green for the second time. I read somewhere on this forum that this was the correct method.
Lately I've noticed, that whenever I pull the spares out, one or both of them are completely discharged. Can't remember the last time I charged them, but I'll guess it was one or two months ago. This is a reoccuring theme. Luckily I have a SF M2 as a backup light.
So is this normal? I thought that cold weather can drain batteries, but it has been very hot lately. Does heat have the same effect on batteries?
How long should I expect these batteries to hold charge, when sitting unused? Do extreme temps make a big difference? Do I have a bad batch of batteries?
While we're on the topic, how many recharge cycles should I expect to get out of a B90? And are there any good B90 replacement batteries out there?
*edited to add: My SF charger is marked CN400.
Last edited:
