What are cheap sources of energy (batteries, accumulators) that can hold a charge for more than a month?

Question

Electronics

The price of the issue is up to 1000 rubles, the device is a small bracelet on hand that works via Wi-fi and / or Bluetooth that communicates with the phone 3-4 times a day, are there solutions for this problem?

Answer 1

KO suggests that for 1000r you can buy a pack of ordinary batteries and which will calmly hold a charge for a month.
The question itself is formulated very stupidly and naively.
For a normal answer, you need to indicate what you are going to power (a bracelet, a phone, or both), requirements for dimensions and weight, voltage, consumption characteristics, operating time from a regular source with an indication of its capacity, etc.

Answer 2

If you assemble the device yourself, then the MK can be completely put to sleep, and "wake" it 3-4 times a day.
In this situation, I think anything with the right voltage will work for a month