EASA published Safety Information Bulletin (SIB) informing airlines and passengers about how to fly safely with Portable Electronic Devices containing Lithium Batteries.
The Civil Aviation Agency of Montenegro, having in mind increased number of travels in the forthcoming New Year and Christmas holidays, published the safety recommendation of the European Aviation safety Agency (EASA) informing airlines and passengers about how to fly safely with portable electronic devices (PED) containing lithium batteries.

EASA, In its Safety Information Bulletin (SIB) recommended that the PEDs containing lithium batteries such as laptops, mobile phones, tablets, electronic cigarettes should be carried in the passenger cabin, to enable the crew to react rapidly in case an incident involving such a PED occurs. The final decision regarding the recommendations contained in the relevant SIB is up to the airlines. 

It is important that Airlines inform their passengers that large PED should be carried in the passenger cabin whenever possible. In case large PED cannot be carried in the passenger cabin due to their size, and therefore have to be carried in checked baggage, they must be :
•    Completely switched off and effectively protected from accidental activation. To ensure the device is never powered on during its transport, any application, alarm or pre-set configuration that may activate it shall be deactivated;
•    Protected from the risk of accidental damage by applying suitable packaging or casing or by being placed in a rigid bag protected by adequate cushioning (e.g. clothing);
•    Not carried in the same baggage together with flammable material (e.g. perfumes, aerosols, etc.);

You can read the Safety Information Bulletin here.

The original edition of the Bulletin of Security Information can be found on the following link:
https://ad.easa.europa.eu/ad/2017-04R1

More information about lithium batteries can be found at:
https://www.easa.europa.eu/easa-and-you/passengers/dangerous-goods#lithium-batteries