Factory 2nd Battery

[rhinoman]

I ordered a second battery from the factory thinking it will be useful to have some surplus power for recharging tools, powering laptop etc, but how do I ensure that the power draw only depletes the second battery and not the main one?

 

[Pauly]

The two batteries are electrically isolated when the ignition is turned off via a relay controlled by the BCM

 

[rhinoman]

So just run a socket or invertor from the second battery and I'm all good?

 

[mhill]

So just run a socket or invertor from the second battery and I'm all good?

Yep!!

I fitted a volt meter in the rear a few weeks ago and although there is a good charging voltage the settled voltage is only 12.3 and it drops quickly with use from LED lamps.

I did have the spec of the OEM battery under the seat and it's a small starting battery, I did contemplate replacing it but came to the conclusion use it, kill it destroy it then replace with something more suitable.

 

[rhinoman]

Do either of you know anything about the posssible issues around using an invertor with a standard 240v charger and it shortening its life?

 

[mhill]

Your wanting to use a inverter to run a 230v charger to charge a battery?

 

[rhinoman]

Your wanting to use a inverter to run a 230v charger to charge a battery?

That was what I was thinking, have few different ones so thought it would be more effective than buying the 12v versions but somebody told me it wasn't a good idea as it destroys the charge by using an invertor so just trying to gather some knowledge.

 

[mhill]

Would you be using this as the main charging method day to day? If so then get a battery to battery charger that's designed to do it.

 

[xpfloyd]

I think he means he will use an invertor to run a battery charger for tools, not for the second battery.

 

[Pauly]

Not aware of any problems doing this but reckon you will need a decent invertor as chargers have a bit more electronics in them now.
@travelvolts may be able to add more but I'm thinking it's not worth risking the batteries on a cheapy as most makita/dewalt etc etc are going to cost you £50-60 minimum each

 

[Loz]

You will also need a decent sinewave inverter as some of the chargers can fry with a cheap inverter.

 

[rhinoman]

You will also need a decent sinewave inverter as some of the chargers can fry with a cheap inverter.

Any recommendations?

 

[Loz]

Not had to buy one for years, I don't like them personally, too much power wasted in the process, I have always preferred to try and find a dc-dc solution but I know it's difficult for power tools because there are just so many different battery types on the tools.

 

[stuart-t6]

I have had a modified sine wave inverter in my work vans for years and use it to charge hilti makita and Bosch battery's and have never had a problem with the chargers or the battery's I have been charging. The only thing it does not like are the small switch mode transformers.
Albeit when this one packs up I will get a sine wave inverter

 

[travelvolts]

You can't go wrong with the Victron 12.375 pure sine wave inverter travelvolts