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I have a whole range of cells bought over many years some NiCad and some NiMH and a couple of odd alkaline ones which unlike the rest are 1.5 volt not 1.2 volt.
I had a really good ΔV charger which could charge up to 12 but unfortunately it died. So I am left with a whole series of chargers some will only charge pairs of cells, some are mains powered, some are USB powered and in the main I have no idea if designed for NiCad or NiMH.
Some have a time out, some have temperature sensors, and in the main instructions have long gone.
Cells at least do say if NiCad or NiMH and have some mAh rating but even the NiMH vary from 800 mAh to 2500 mAh, but since no idea what size the charger is designed for how can one be sure the batteries are charged, but not over charged?
I tend to use the finger test if warm I assume charged if electrical energy is being transferred into chemical energy no heat but once charged the electrical energy is being transferred into heat one charger I have the instructions for does say it will switch off when temperature reaches 65°C or charging time has elapsed but that time varies with capacity of cell from 12½ hours for a 2600 mAh to 6¼ hours for a 1300 mAh as to 800 mAh not even listed.
It was after coming to use the Philips SCB5050NB I decided to ask the question how can one work out what type of charger and what needs to be done to ensure fully charged cells without damaging them by over charging?
The charger is USB and fit one pair of batteries, and red charge lamp comes on. Put in a second set and lights go off, swap the USB lead from one powered USB hub to another powered USB hub or Lap top and lights work with two pairs of batteries. Clearly the one hub can't supply enough power, but raises the question how do you know if charge completed or hub overloaded? Charger says Input DC 5.0V 500 mA which in theroy should allow it to work in any USB powered hub but not it practice.
Main use of cells is to power my photography flash guns, so I want to go out with a couple of sets for each flash gun so need 8 cells 4 in use and 4 spare. The 800 mAh I have found useless around 6 flashes a pair, but the 2500 mAh will last more like a 100 flashes not 20 as one would expect being just 3 times larger. But they have to be fully charged.
I am sure I am not the only one to use AA Cells, unlike lead acid volts don't help. But my camera also uses NiMH and has an indicator to say how much charge is left, as does many items that use NiMH so there must be a way to work out state of charge, but how?
I had a really good ΔV charger which could charge up to 12 but unfortunately it died. So I am left with a whole series of chargers some will only charge pairs of cells, some are mains powered, some are USB powered and in the main I have no idea if designed for NiCad or NiMH.
Some have a time out, some have temperature sensors, and in the main instructions have long gone.
Cells at least do say if NiCad or NiMH and have some mAh rating but even the NiMH vary from 800 mAh to 2500 mAh, but since no idea what size the charger is designed for how can one be sure the batteries are charged, but not over charged?
I tend to use the finger test if warm I assume charged if electrical energy is being transferred into chemical energy no heat but once charged the electrical energy is being transferred into heat one charger I have the instructions for does say it will switch off when temperature reaches 65°C or charging time has elapsed but that time varies with capacity of cell from 12½ hours for a 2600 mAh to 6¼ hours for a 1300 mAh as to 800 mAh not even listed.
It was after coming to use the Philips SCB5050NB I decided to ask the question how can one work out what type of charger and what needs to be done to ensure fully charged cells without damaging them by over charging?
The charger is USB and fit one pair of batteries, and red charge lamp comes on. Put in a second set and lights go off, swap the USB lead from one powered USB hub to another powered USB hub or Lap top and lights work with two pairs of batteries. Clearly the one hub can't supply enough power, but raises the question how do you know if charge completed or hub overloaded? Charger says Input DC 5.0V 500 mA which in theroy should allow it to work in any USB powered hub but not it practice.
Main use of cells is to power my photography flash guns, so I want to go out with a couple of sets for each flash gun so need 8 cells 4 in use and 4 spare. The 800 mAh I have found useless around 6 flashes a pair, but the 2500 mAh will last more like a 100 flashes not 20 as one would expect being just 3 times larger. But they have to be fully charged.
I am sure I am not the only one to use AA Cells, unlike lead acid volts don't help. But my camera also uses NiMH and has an indicator to say how much charge is left, as does many items that use NiMH so there must be a way to work out state of charge, but how?