Increasing battery life of smart lock

[cal6404]

Hi,

I have a smart lock that runs of 4 double A batteries in series (I think its series). I want to increase the length of life of the smart lock as it only last 5 days! I was thinking of running a car battery to power pack and remove the double A batteries. My impression is that 4 double A's is 6v. Therefore if i get a 12v car battery and use a cigarette lighter that converts the 12v into 5v then i can then run the 5v usb cigarette lighter into the 6v battery pack that has the batteries removed. I would think the smart lock could urn of 5v since it so close to 6v (also when the batteries start to die it will end up providing 5v anyway so it should work).

Is this logic correct? Would this work or would i break the smart lock. Is amps an issue here? Thanks

 

[Audioguru]

You need to measure or calculate the current needed then buy an adapter that provides that much current or more.
Cheap Chinese "super heavy duty" battery cells might be a few years old and power your lock with a few mA for 5 days. Fresh Name Brand Alkaline battery cells can supply hundreds of mA for 5 days. Maybe the good battery will fix your problem and last for months.