Intermittent electrical problem whilst driving

[TB83]

Morning all. 
 

Rav4 2.2 2013 85k 
 

Tried to scour the forum for an answer, so apologies if it’s already being covered. 
 

I have had an issue over the last month, 1st problem was the EPS light flashed on going round a corner, power steering loss for about 2 seconds. Then nothing for 3 weeks until last week driving back from the lakes, going round a corner it appeared all dash lights flashed on including abs, going round a corner, lasted about 5 seconds and then normal driving all the way home. 
 

Yesterday, again going round a corner and dash lights on and lost power steering for a few seconds and then pulling into my road a few miles later lights on again, this time traction control message stayed on for about 10 seconds. The problem is when it’s happened I’ve not had time to asses which lights are before it goes back to normal. 
 

Another weird thing happened twice over last month too, I’ve gone to to my car and it’s as if the Battery has been disconnected, opened the door and there’s nothing at all, no lights on dash, then I close the door and open again it’s back to normal. 
 

Got it straight into my workshop and checked Battery, readings all good with Battery on and off. 

Going to get into garage next week, but is it possible the battery could just need replacing? 
 

many thanks