Leisure Battery Charging

[Beata]

Hi all,

I am a new to the forum (literally have just signed up). However, have been following few threads and found it very helpful. Now I am hoping someone may help me with understanding the second battery charging system as what I read online does not agree with what I have heard from mechanics.
I have just bought T6 Transporter 2016 and want to put the Lithium battery in it. T6 has a smart engine and I read that the battery to battery charging system is the way to do it. However, when I talked to different people they said it is ok to do a spilt charging and only newer 'switch'is needed. Apparently the one used for T5 wouldn't work but they said I could get one for T6. They advised CBE.
Could you tell me if:
1. this is correct that split charging will work for my smart engine?
2. what way of charging would be more efficient for my type of battery, (if this makes any difference)?
3. if I use split charge system - will I loose the warranty for an alternator?

Thank you so much!

Beata

 

[travelvolts]

Hi Beata, welcome to the forum. You have been given completely wrong information. Charging with any kind of relay does not work. Not only will it not charge your battery but it can also damage it due to high voltage generated during braking regen phase.
CBE do not make a suitable product. See here for suitable DC-DC charging systems Electrics | Travelvolts

 

[Jollyvan]

I went down the Lithium route at first with a Ring unit. Travelvolts might give you better advice but due to the way a Lithium battery delivers its power the DC/DC unit could not manage the power as it supplies power on a very flat curve and suddenly drops off. This seems to be a problem for DC/DC units. Went for a gel battery and solved the problem. Hope this helps.

 

[travelvolts]

Totally agree. I missed the bit about the lithium battery

 

[Evelyn]

I am also new to the forum and indeed to life with aT6 conversion. I am having difficulties with the charging of the leisure battery which I believe is using a non factory split system. The conversion company tell me its a fault in the vehicle battery system however VW state that the split charger will not work on my T6.
Anybody with a similar issue

 

[DaveyB]

I am also new to the forum and indeed to life with aT6 conversion. I am having difficulties with the charging of the leisure battery which I believe is using a non factory split system. The conversion company tell me its a fault in the vehicle battery system however VW state that the split charger will not work on my T6.
Anybody with a similar issue

Are you able to give us an idea as to what split charge system is fitted to the van? Do I take it that it was installed prior to the converter doing their work?

 

[Evelyn]

It wasn’t factory fitted. Supplied and fitted by the converters. I will try and find a make

 

[travelvolts]

If it is a conventional split charge system it won't work. Plain and simple. Sadly, there are still some converters out there with their heads firmly in their backsides on this subject. Take it back to them and demand to have it put right.

 

[Evelyn]

Thank you for this response. I have contacted the company and I await their reply

 

[Beata]

Travelvolts and Jollyvan thank you for your response. I have done more research and can see that the lithium battery is so problematic due to the fact that there is not many people who understand the issue associated with it and I have decided against it since I am not an expert myself.
I am in the process of choosing what I want and decided for AGM Super Cycle Victron battery 125AH battery. My main battery is AGM as well so hope this should work fine, right?
I am not going for B2B at this stage as I do not won't to loose warranty but will go for solar panel.
Could you guys double check if what I have chosen will work together or suggest the products with 'righter' parameters.
Battery as mention above or should I go for gel one? I have chosen AGM as it seems to be no maintenance compering to gel one.
Battery charger: Victron Blue Smart IP65 12V 10A or I have seen Blue Smart IP22 Battery Charger 12V/15A/230V - 1 Output - CEE 7/7 Socket. I would like to have the charges with the few stages charging.

Inverter: Phoenix 12V/375VA/230V <----this is something I have no clue at all, so if you could suggest something more suitable/better I open for suggestions.

Solar panel 150W, controller Victron Energy MPPT12V/24V 100/15

What about control panel? Should I go for one such as battery control only (the I though of BMV-700 Victron). Actually what else will I need to control? hahaha

Thank you in advance for your advice.

Very confused new member

 

[Beata]

Or what about this charger
Sterling 'Pro Charge Ultra' Battery Charger - 12V 10A?

 

[travelvolts]

A 15 or 20 amp charger would be better suited to your choice of battery, especially as you are not having DC-DC charging. The battery choice is good and so is the solar set up. What are you planning to run from the inverter?

 

[Beata]

Hi travelvolts, thank you for coming back to me. I noted what are you saying about charger and will search for 15 or 20 amp one - thank you for your advice.
Re inverter: I will be using it mostly for laptops, camera battery charger and mobile phones as my compressor can be charged via 12V socket.
Please advice what you think as inverter's description is a bit sci-fi for me.
Thanks a lot!
Beata

 

[travelvolts]

The Victron 12/375 will be fine for what you need. Electrics | Travelvolts

 

[Dieseldonkey]

Reading this with interest. I understand AGM batteries like a higher charging voltage. However other than taking longer to charge, is there any detriment to the battery if a low charging current is applied?

 

[travelvolts]

Charging with a lower current is always kinder to a battery so is preferable if you have the time.
All multi stage smart chargers like Victron and Ctek will choose the best algorithm for your battery at any given time. About 20% of battery capacity is the recommended max charging current.

 

[Pocc]

I've datalogged various split charge systems on T6 and can say there is a lot of mumbo jumbo out there in relation to stop/start, intelligent alternators, regenerative braking etc etc. Our split charge solution works, IS via a CBE system and does not affect the vehicle systems at all (and before everyone says it can't be done, as I say I have the voltages and currents datalogged both pre and post conversion to prove it works). Unlike most converters the stop/start and regenerative all still work as designed in our vehicles.

What is correct is that you can't just use a voltage sensing relay and old style 'leisure battery' as a split charge system anymore. Battery to Battery chargers are voltage sensing solutions but tend to have a time dependant algorithm rather than 'chattering' the way old voltage sensing relays did. They also contain FETs to limit the voltage being sent to the aux battery and thus prevent overcharging dependant on aux battery type used.

Internal resistances and voltage fluctuations from the freewheeling alternator and liion or lithium batteries nowadays mean that you run the risk of deep discharge and rapid recharge of either the aux battery or worse the vehicle battery and systems if you do not match battery types and capacities. This buckles plates in batteries faster than hitting them with a sledgehammer and seriously limits the life of batteries and systems.

One last comment on your set up; you never get anything for free when it comes to energy. If you're planning on charging the battery via a 100w solar panel and hope to take it out with a 375w inverter- which will probably suck say 450w out the battery - around 40 amps - your battery life will be measured in minutes not hours

 

[travelvolts]

Interesting. What CBE system are you referring to here? FYI, the Victron Cyrix VSR also has built in circuitry with time dependant algorithm to prevent chatter, so this is not something that is limited to DC-DC chargers.

 

[Pocc]

Interesting. What CBE system are you referring to here? FYI, the Victron Cyrix VSR also has built in circuitry with time dependant algorithm to prevent chatter, so this is not something that is limited to DC-DC chargers.

Hi Travelvolt, yes you're quite right about some VSR's having a time delay and I guess what we should also mention in simplistic terms is that DC-DC chargers limit the output VOLTAGE to a charging voltage whereas VSR's just close a switch and link the batteries - allowing deep cycling to occur and allowing the excess voltages from the smart alternator to reach the aux battery and cook em good

We can use any CBE system with the DS300 controller which does modify the charge voltage as the FETs are using this to limit the charge current to a max of 20A. The secret is finding the right connection (not D+ or engine running) that stops the DS300 'unlinking' when the alternator idles on coasting or when the vehicle battery is sensed as having sufficient charge. This also prevents deep cycling of the battery link which has spurious effects on the stop/start.

If you use the CBE DS300 it has the added benefit of meeting Reg 10 for disconnecting the 'camper' circuits whilst the vehicle is in motion and helps avoid all those nasty 'E' numbers!

 

[travelvolts]

So, share the secret then because unless I am very much mistaken the DS300 has a 70 amp ignition controlled relay and is not a DC-DC charger??????? For self converters Reg 10 is of no interest so nothing gained there. Do you work for CBE or something?