Yes you can. I answered a similar question to this a few weeks ago. The mAh figure is simply the capacity of the battery. So long as it's the correct dimensions and voltage - it will be fine. I have a Sony Ericsson mobile - which had a 600 mAh battery in it. I replaced it with a 950 mAh battery - which has extended the time between charges.
No reason why not. So long as the physical size of the battery matches, and the voltage it delivers is the same - you should be able to replace it with the higher mAh battery.
Yes as long as both the 2450 mAh battery and 600 mAh battery have the same voltage. The larger one will just last longer and take longer to charge up (I am assuming these are the solar powered type lights).
Yes, you can replace a 1.2V 400 mAh rechargeable solar light battery with a 600 mAh battery, as long as the new battery is compatible in terms of size and type (e.g., NiMH). The higher capacity of 600 mAh means it can store more energy and may provide longer usage time between charges. However, ensure that the solar light's charging circuit can handle the increased capacity without issues.
Sure, if they have the same voltage.
can use 1400mah battery to replace 760 mah
No
Yes and no. The higher capacity battery will last longer, but you need to consider the charger. It depends on the design of the circuit.
A 600 mAh battery can produce 75 mA for about 8 hours. If it is called upon to deliver 600 mA, it will last somewhat less than one hour. This is because ampere-hour ratings for batteries are, by standard agreement, normalized to an eight-hour rate. The actual rating is only a comparative rating, so you could properly say that a 900 mAh battery, for instance, will last 1.5 times longer than a 600 mAh battery.
mAh stands for milli ampere hour and it is a measurement of how many milli amps of current a battery is capable of producing in one hour. Yes you can substitute a battery with a higher mAh current rating provided you use the same battery voltage.
Not a good idea. It will work but not as long as the 1000 mAh battery.
No, a 1000 mAh battery should not replace a 400 mAh battery in solar lights unless the system is designed to handle the higher capacity. Using a battery with a significantly higher capacity than what the system is designed for can potentially damage the circuitry and reduce the efficiency of the lights. It's best to stick with the recommended battery capacity for optimal performance.
In general, no. The charger is designed for a specific battery profile, and it might not be able to properly charge and/or monitor the amount of charge if you put in a different battery.