You cannot charge it connected backwards. You will destroy the battery.
No
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.
Charge it with a 12 volt battery charger.
The battery will attempt to charge the charger since the battery is at a higher voltage than the charger. Thus, the battery will simply discharge and generate heat. If you leave it plugged in long enough, eventually the battery will discharge to a point where it can maintain only 6V, where it will stay until you actually charge the battery.
It is not recommended to charge a 6 volt battery with a 12 volt battery charger as it can damage the battery. The higher voltage can overcharge the battery and cause it to overheat. It is important to use the correct charger with the matching voltage to prevent damage to the battery.
You do not charge a 7.2 volt battery with a 9.6 volt charger period unless you want to ruin the battery. You charge it with a 7.2 volt charger.
No it will not work
no it can't
It takes about 6 hours to charge a 7.4 volt battery when using a 5 volt charge. For the best results try charging it over night.
No, a 12 volt charger will overcharge a 8 volt battery and destroy it.
No, an automobile battery charger outputs 12 Volts. This is far too many volts to charge a 5 Volt battery. You would destroy the 5 Volt battery with this charger.
No you cannot.