Move the starter battery inside

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Updated – December 29, 2022

At some point the lifespan of the vehicle battery will come to an end. A replacement of the same is imminent and the considerations of how to replace the old battery in the - installed - engine compartment of the fully integrated vehicle with a - perhaps larger - new battery are becoming increasingly important.

A larger battery equals an increase in weight and spatial size. The latter aspect is usually the limiting one if you have the same installation location for the battery in mind.

But what if you move the battery indoors? The spatial increase in size no longer plays a major role. It is also more protected from frost than in the engine compartment and is therefore easier to start in winter. Aging caused by external temperature influences is also counteracted, which in turn protects finances for longer.

In addition, you have more freedom when choosing batteries and can choose “mass-produced goods” because you are free from any “rare” design. And – last but not least – the fuses installed on the plus pole of the vehicle battery can also be accessed quickly.

Now, interior installation is not per se a simple solution if you want to keep the existing features of a fully integrated vehicle unchanged. The proposed variant is actually ruled out. But if you are flexible and don't mind converting the passenger side panel, this advantageous option is available in the form of the former step on the passenger side. Its height and width fit exactly for a battery with standard dimensions.

Ultimately, it is important to keep the cable routes as short as possible, which is due to the close proximity of the new battery position directly behind the right front wheel arch in the interior. In the future, starting assistance will be available via the passenger window.

If the plus/minus cables are to be easily separated, the extension of the plus/minus cables can be done with a High current connectors be implemented for 50 mm²– Cables can be connected using the crimping process and loaded with around 300 A or, in the usual way, as a direct cable connection.

The chassis-side plus contact is equipped with four fuses. These cables would also have to be (!) extended accordingly with cables of identical cross-section and suitable connectors or compression sleeves.

The fuses are (according to FIAT Ducato manual):

• 150 A – Control unit protection CVM distribution (engine compartment) – Fuse No. F70
• 80 A – backup fuse for the CFO distribution (right footwell) – fuse no. F71
• 100 A – Alternator (2.8 JTD and 2.0 JTD A/C) – Fuse No. F72
• 70 A – installer socket (EBL / isolating relay – body supply) – fuse no. F73

Attention: There are no replacement fuses on the vehicle for these fuses (as there are in the other fuse boxes). It is therefore advisable to purchase these separately and keep them within easy reach. Of course, once you have it, you will probably have it. never need.

The plus cable of the starter is not fused and is routed directly to it.

If you want to avoid extending the various cables and leave the fuses where they are, there is a very practical alternative solution with just two 50 mm²– Cable (plus/minus).

Both 50mm² Cables are routed into the side engine compartment via two separate 20 mm holes, which are made on the passenger side from above through the foam insulation and the PVC panel underneath.

From there, the respective length is measured, the cable ends are stripped and the tubular cable lugs are pressed on. Only hydraulic presses are recommended for these calibers.

The fuse carrier of the positive pole battery terminal has an M8 hole through which a suitable tubular cable lug connector for the 50 mm can be neatly connected² Positive cable is possible using an M8 x 35 mm screw, washer, lock nut, washer, tubular cable lug, washer and lock nut.

The plus cable must be stabilized with a cable tie at a suitable location on the chassis to prevent the fuse holder from coming to ground.

The negative cables of the dismantled negative pole battery clamp are attached to one of the two available M8 bolts on the left in front of the battery holder (usually painted over white and removed from paint using a thread cutter) together with the new 50 mm² Negative cable screwed using a lock nut.

Charger for starter battery

If you have Victron components installed anyway, this is an option Victron Blue Smart IP22 12V/30A at. It can be administered via Bluetooth and the current functional status can be queried. Thanks to its compact design, it fits directly to the right above the former step and can be removed using a short 10 mm² Cables are connected to the battery connections.

The charger is connected to 230 V via a separate line that is protected by the fuse distributor via an additional fuse.

DC/DC charging booster

When driving, the battery is charged via the charging booster Victron Orion-Tr Smart 12/12V 30A loaded. This should be positioned in the immediate vicinity of the body batteries, as the booster automatically compensates for the voltage losses via the supply lines starting from the starter battery.
Even if it can compensate for the voltage loss, this should not encourage you to use thin cables. The more it has to compensate, the less charging power and heat loss results.

Cables with 35 mm² Fit well with wire end sleeve, 50 mm² only without a wire end sleeve and very narrowly into the screw terminals of the charging booster. In this respect, if the installed cable length allows it, it is 35 mm² to prefer.

For longer cables and 50 mm required² can be found on the Plus page for this purpose ANL fuse holder just before the battery to 35 mm² be reduced. Lt. According to the data sheet of the charging booster, a 60 A fuse must be installed in the plus cable just before the battery. On the minus side, a connection terminal is required for reduction.