There are simple power strips and power strips with surge protection (and also with short circuit protection). Is there difference in that matter for PCs and laptops? If I use laptop I have a battery (does this protects me from such stuff) and a power adapter on the power cord. May be the adapter does something, doesn't it?
Short answer: Yes
For laptops and mobile electronics, I always recommend surge protectors that use resettable circuit breakers, such as Panamax's Power360 Wall Tap (auto-senses under-voltage and over-voltage, auto tripping and resetting its internal breaker when required, providing a LED ring with three diagnostic lights).
- Using any externally powered electronics without a surge protector risks permanently damaging those electronics when a surge occurs (it's not a matter of if, but when)
A battery is simply there to power the device, not absorb fluctuations in voltage and amperage the way a vehicle's battery does; small fluctuations are dealt with via the AC-to-DC power adapter/brick.
- Lithium-based batteries require a very specific charging voltage and amperage range - they are not there to absorb a voltage/amperage surge, as doing so could have serious repercussions from heat damage
- If the battery temp rises high enough from over-voltage/current, it can melt it's hermetically sealed electrolyte which burns explosively when exposed to oxygen
A surge would likely only fry the laptop's power brick, but whether any of the excess voltage/current could pass to the laptop is dependent on the internal design of the power brick.
Surge protectors should be purchased based on Joule rating (higher Joule rating = better).
- Surge protectors, excluding those with resettable circuit breakers, have a finite lifespan and can only be reliably used for a few years, usually two to three years is what most manufacturers guarantee.
- Non-resettable circuit breaker protectors are one-time use only protection items - once a surge occurs, the surge protector needs to be replaced.
A laptop battery can protect against low level fluctuations and short term power outages and subsequent power restarts.
The AC input has a range of input voltages and the battery provides basic power to accomplish the above.
But that does not protect against a major power surge like a lightning strike. You still need a surge protector for such events.
We have (and have had) clean power here so I do not equip my laptop with a surge protector because the need does not exist (greater than 99%)