Battery keeps going flat

Findif

https://www.argos.co.uk/product/2010232 would this do the trick to test it ? I can pick 1 up straight away.

My car hasn't broke down yet. But I can tell it's struggling start in the morning. (Slow start noise)...

Also my mains charger I have at home. (Away for work atm) its called Smart trickle. Has these 4 or 5 lights when u put it on battery when charging and shows you how low the battery is. Does that do a similar job ???

mchale

Listen to the info given in post 10, that's the most sensible

Rolandtheroadie

Multimeter every time.

First reading, charging voltage. My last 2 cars charged at 13.8v. Not enough for the car involved or the journeys it was used for.

Second reading, battery. I'd check the night before, then again in the morning. 12.4/12.5 when parking up, if it was down to around 12.2/12.3 the next morning, the car would struggle to start, or wouldn't start at all.
Finally, check for parasitic battery drain. If there wasn't any, I'd replace the battery.

Worked fine for me over the years.