miggit wrote:

How big do you want to go?

You can already get a 110Ah battery under the hood and fit the same in the back and you'll have 220 Ah, any bigger and you'll be robbing a big rig for a battery

OK so I got the sizes slightly wrong..... was only trying to help

I did suggest that the OP tried a new 020 AGM in the engine bay FIRST before adding another battery.... so the 020 wont fit in the boot box, so fit a 019 AGM which is the same height, width and 2" shorter..... it is only 95 Ah....AND?

The other observation is the AGM batteries have a smaller Ah than the wet batteries, I thought that the 020 was 110Ah.... turns out it's 105Ah...... but that's still a combined capacity of 200Ah AGM which are a high duty cycle and will take multiple discharge / recharge cycles in their stride  Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

Weejock wrote:

What extra electronics have you installed that should effect the drain that much that starting is now a problem?

Ah ha..... we now have a eureka moment Assuming that your HSE is a 2002 - 2005 car, then the problem is the power socket in the trunk is always live..... you may as well leave the headlights on as well, and really do the job properly

All is not lost however.... as you have used the accessory socket in the trunk, there is the aux fuse board behind the panel next to the socket, I would go in there and find a power feed that is only live when the key is turned and wire to that..... FYI the best way to do that is use a relay, switch the relay with a tap from the switched live, and then feed the main power part from the large + on the panel..... that way you'll get a switched live, and the car wont be having a party without you  Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

It's actually a 2010 supercharged. And the cargo socket is unplugged every time I get out the car as a precaution. This morning the car didn't start up after sitting for two nights straight. Battery voltage was at 9.8V. Took my car into the dealership this morning for it's 75,000 mile service, mentioned the battery issue and they said you're not gonna get more than about 20 minutes on battery before the system shuts down - claims this is by design. They're going to test the battery, test for unexpected power draws, etc. (says car shouldn't be drawing more than 0.35 A when off).

Also says customers haven't had much luck with AGM batteries in these - claimed it just didn't work/startup for some. Recommended I stick with Interstate Batteries brand (was going to get the DieHard AGM battery).

I'll let you know what they find.

I'm shocked that they haven't tried to flog you an OEM battery.... as I very much doubt that Interstate are the make that the car is supplied with..... I could be wrong, but I would have expected it to be a German / British brand... Still if your car's 6 years old it could be the original battery and it's just got to the end of it's life.... most are rated at 4-5 years.... you know that they aren't going to warranty something that isn't expected to go the distance.... Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

Dealership tested the battery and it failed. That solves that mystery.

I'm no longer interested in Optima yellow top batteries (under hood/bonnet nor in trunk/boot) - too many folks reporting issues with them in the last couple years (reliability seems to have tanked since they moved it's factory/manufacturing to Mexico years ago).

I'm still interested in an AGM type of battery (despite dealership's advice... I love trying and failing anyway) so I'm going with a DieHard Gold AGM since it features 120 more CCA and close to the 100 Ah capacity of the failed/outgoing lead acid battery. Plus it's $200 cheaper than the same model replacement the dealership sells.

Good Luck Buddy

Fyi a dealer is never going to recommend non standard part... it would be admitting that the factory got it wrong to start with.... they'd have the lawyers queuing up at the doors

I have no experience of the AGM batteries, but there have been a few on here that have fitted them.... haven't seen any complaints........ Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

I use an O'Rileys Auto Platinum I think size 49 and 110 ah. It is an AGM. Sears AGM seems cheaper. I think almost all of the AGM batteries (sold in the US) are made by the same company in the USA. I would go AGM personally.

They don't sell british or european batteries here afaik.  OffRoadRover.com An American Western Range Rover Off Road Blog

The battery is rated at 730 A, but when they tested it it could only put out 306 A. The battery was installed 3 years and 2 months ago, which means it was a replacement and the battery it replaced (most likely the original battery) also mustered about 3 years. Is this the normal lifespan of lead acid batteries with these vehicles?

Either way they replaced it with the same model - they already had it removed since they were checking the warranty, so I got lazy and said they can replace it. AGM will have to wait until this dies in 3 years.

Now, I'm shifting to the next option; battery in the trunk/boot. Any known lead acid batteries that'll fit there?

miggit wrote:

Have a look at this

http://www.fullfatrr.com/forum/topic26065.html?highlight=battery

bruzer wrote:

The battery is rated at 730 A, but when they tested it it could only put out 306 A. The battery was installed 3 years and 2 months ago, which means it was a replacement and the battery it replaced (most likely the original battery) also mustered about 3 years. Is this the normal lifespan of lead acid batteries with these vehicles?

My ffrr has a Bosch battery in it and it's a 5 year warranty so the answer to your 3 year question is.. yes if you fit cheap batteries, no, if you fit a quality item, which from what I gather is of no use to you as you have the option of cheap and expensive cheap quality, D'OH!

As for battery options for the boot / trunk, as long as it's 190mm (7 31/64")heigh, 175mm (6 57/64")wide and less than 354mm (13 15/16") long then it should fit.  Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

I had to replace the batteries in my wife's mobility scooter last week.

When I pulled the old batteries, I thought "Hmmmm. I wonder?"

I found that two 45Ah deep cycle VRLA batteries fit perfectly into the well at the back of my L322. I'll wire them in parallel for 90Ah capacity.

The batteries I bought for the scooter are Neuton Power NPD12450. I'm buying another two for the Rangie.

Dimensions and Weight
Length ( mm / inch )………………………………....196 / 7.72
Width ( mm / inch ) ………………………....…...…166 / 6.54
Total Height ( mm / inch )………………..………..175 / 6.89 Ron B. VK2OTC
2003 L322 V8 Auto
2007 Yamaha XJR1300
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