So I have replaced the battery on my car after a few episodes of poor starting.
Went for the huge Varta battery suggested elsewhere on these forums.

The new battery is showing the occasional poor starting symptoms as well.

Admittedly my car rarely gets a decent run with my daily commute being a 6 miler each way. The engine isn't fully hot according to the temperature gauge. I no longer use the heated seats or steering wheel unless going on a longer drive to reduce the load on the battery. The cold weather isn't helping either I'm sure.

Is it common practice to charge the battery occasionally ? Current: Supercharged 06 FFRR in Java Black
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I've replaced mine at xmas and it only starts to show signs of battery depletion after about a week of not using it.. short runs about town don't help me either. Maybe new needs a good run a couple of times a week to keep it tip top..wouldn't do any harm connecting it to a battery conditioner. I got one of those £15 trickle chargers for Aldi and it's worked great..if I know I'm not going to use the car for a week or 2 I hook it up for a bit

If you are doing very short journeys each day your battery will be getting a bit of a hammering. Quite normal to keep it on a charger with the capability of conditioning charge e.g. Ctek. John
2008 Stornoway Grey 3.6 Tdv8 Vogue
2005 TD6 Java Black Vogue - Written off!!
GAP iiD BT
2003 Discovery TD5 Auto, Nanocom Evolution - gone to a new home!
MasseyFerguson 152 - No electronics!! - Sold

Thanks for the quick replies guys... that helps a lot and confirms my suspicions.
The old battery was actually perfect after all and is now a backup of required. Current: Supercharged 06 FFRR in Java Black
Previous: BMW 740D M Sport
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A wee update... so fully charged the car battery Saturday and then Sunday morning drove to Newcastle from Glasgow. So no shortage of a decent run and no real reason for poor starting issues.
Car was fine yesterday all day.
Out to it this morning and click, nothing from the starter motor. Electrics all powered up fine.
Turned off and tried again, click
Off again and click.

Tried again and success.

Is there a pattern of starter motors failing ?
Any suggestions from the hive mind of owners ? Current: Supercharged 06 FFRR in Java Black
Previous: BMW 740D M Sport
Previous Previous: BMW 730D Sport

I was speaking to the owner of a 2010 TDV8 the other day and he had had a starter motor replaced, said it was a known issue.

Could you have a loose connection somewhere? My experience of battery drain was that it left you with nothing, rather than intermittent non-starting. Only Range Rovers since 1988

A loose wire is a bit unlikely imho The car has travelled 400+ miles in the last 3 days alone... Current: Supercharged 06 FFRR in Java Black
Previous: BMW 740D M Sport
Previous Previous: BMW 730D Sport

Are you confident that the charging circuit is working properly? Even a good battery won't behave well if it's not being charged properly. Things to look out for are the charging voltage when the engine is running, at idle at at say 3k revs; are both battery terminals definitely done up tight; check for any significant voltage drop between alternator B+ terminal and the battery positive; or the battery -ve and any body earth.

What is the actual behaviour when it fails to start? Does it turn the engine but is just sluggish? Does it just 'click' and not turn the engine over at all. If you have headlights on and try to start it, do the headlights go out?

All these things will give a clue to what is going on. Could be many things - failed voltage regulator or alternator diode pack; a dodgy ignition switch; faulty starter relay or solenoid; faulty starter motor; dirty connections or faulty starter cabling; could even be a dud cell in the new battery, though that seems unlikely.

If you're not sure where to start, a good auto electrician will work their way through this in next to no time and could save a lot of heartache and 'try it and see' fault finding. Current: 2010 Range Rover L322
Vogue SE, TDV8 3.6, Bournville
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Now gone: 2002 Range Rover L322
Vogue, TD6, Giverney Green