The charger will most likely work.
NO, voltage of the charger must match the battery voltage.
No, you cannot charge an 8 volt battery with a 6 volt charger. The voltage of the charger must match the voltage of the battery.
No, the battery charger has to match the voltage of the battery it is to charge.
Chargers don't care is the battery is used on a boat, a car, or whatever. What is important is that you match the voltage of the battery and the charger. Don't use a 12volt charger on a 24volt battery, etc.
You have to compare the Output of the charger. The voltage is most important. For example: If the ES55 charger puts out .5 Volts and the iPod charger puts out .5 Volts then the voltage is compatible. Both the iTouch charger and Samsung Galaxy Appeal puts out .5 Volts. The Amperage should be near similar, but is not so important since a battery does not draw more than it can handle. The next question is connecting capability. Just try it out if the voltage and amperage match.
In some instances a charger can be used in place of an AC adaptor. The one thing to keep in mind is that the output of a charger is not filtered as other power supplies are. The output of a charger will have a high degree of DC ripple voltage.
It is important for solar battery charger output voltage to match voltage of battery system being charged. Voltage is additive in series circuits, therefore 3 12VDC solar battery chargers connected in series would provide correct output to charge a 36VDC system.
This is not advised! The 9-volt charger might have a current limiter so that nothing burns up, but it any case if left on it will destroy the 6 volt battery by overcharging. A 6-volt charger is not expensive.
Some have a switch for 6 or 12V - if not you will "cook" a 6 volt battery using a 12 Volt charger
To match 2 phase line voltage it has to be the same voltage.
The part number needs to match the old charger. Even if if the watts, volts, and amps match; there is no garuantee that the polarity of the pins will be the same.
A car charger does not have to match the brand of the cell phone. There are many car chargers that are compatible with many cell phones.