Victron IP65 battery charger 15amp or 25amp?

[Newcs]

I’m looking for some guidance please

I have a 110amp agm battery (which will eventually be replaced with a lithium one.

I have the 30amp dc to dc Victron charger and I ordered the 15amp mains/hook up charger. I went with the 30amp for the speed of the charge when driving round but I’m unsure if it’s as important with the mains charger.

My question is - is the 15amp enough or should I go for the 25amp version?

My thoughts are it will charge faster however is this such a big deal when it will be plugged in anyway before any trip or on a hook up whilst away? Will I benefit from the additional cost bearing in mind it’s around £40 extra and I’ll have to pay £10+ to return it.

Any help or guidance will be appreciated.

 

[AussieMick]

If you are thinking of changing to a lithium battery one day make sure your mains charger is suitable for lithium as well.
Saves buying another one later.

I have a 150ah lithium lifepo4 battery and my charger is 15amp. This charges the battery fairly quickly as I leave
it on 24/7 if I am running the fridge in my van. I have the same brand lithium charger as my lithium battery and spoke to the manufacturer about leaving it hooked up and they told me that was OK.
I feel the battery temperature with my hand occasionally if I'm passing but that is me being careful and it's never been hot.

25amp will charge it quicker but I've never had a problem in over 5 years of use.

 

[Newcs]

that’s good to hear. It’s definitely compatible with lithium so should be future proof. I’m swaying to the 15 as I think it’s more important to charge quicker on the dc to dc

 

[4wdMotion]

I have similar setup in many ways to AussieMick (also downunder, but in WA) with lithium 150Ah battery and the Victron 15A charger. Only use is before we setup to go and running the fridge down to temp and if we are ever plugged in at a campground. With 2x120W solar on top as well, we feel we are happy with the setup for charging.

 

[Bigsidavies]

I have the 15 and it’s fine. Consider that it’s only for EHU so even with a flat 150ah battery it will charge it in 10 hours. Add a bit of time if you are using 12v appliances at the same time, but you are unlikely to be on EHU on a site for less than 10 hours so it shouldn’t really be an issue.
Another thing to consider is heat. I genuinely don’t know if the 25 gets hotter than the 15 but if it’s in a small space then that might be worth looking into. My 15 only gets warm. Never been hot.

 

[Dellmassive]

there are size differences as well, so check the dimms. . . .

if your looking at the IP22 range, they have a fan - but also low power mode that runs fanless at night.

the IP65 range are fanless and external rated.

 

[Newcs]

I’ve got the IP65 15amp and think it will do the job. Not sure the additional expense can be justified on the 25amp model.

Thanks everyone

 

[Oceanis]

Most LiFePO4 batteries have a 1C max charge rate - for a 100Ah battery, this is 100A. The max charge rate is not recommended to be used regularly as it reduces the life of the battery. 0.3C to 0.5C is the range to look for as the sweet spot between charging time and battery life. 0.3C for a 100Ah is 30A. 15A will take twice as long to charge but the decision is yours so go with what you are happy with. 15A will work fine. Lithium batteries have a much lower internal resistance than lead, so will draw pretty much anything a charger will throw at them - that's why you need a DC-DC to limit the current a Li battery can draw from an alternator (in addition to the different charge profile).

Do bear in mind that when on hook-up overnight the charger is running the 12v system on the van too - so dependent on your 12V loads the charger will not deliver the full 15A to the battery.

 

[Newcs]

That’s great info, thanks.

Given that info, I suppose the question is, is the charger likely to keep up with the usage (heater, fridge, lights, usb whilst on EHU? If it can then it should he fine, if not then an upgrade will be needed.

Time wise, charging from home is fine as this would be done well in advance of leaving for the trip so that shouldn’t be an issue.

 

[Oceanis]

That’s great info, thanks.

Given that info, I suppose the question is, is the charger likely to keep up with the usage (heater, fridge, lights, usb whilst on EHU? If it can then it should he fine, if not then an upgrade will be needed.

Time wise, charging from home is fine as this would be done well in advance of leaving for the trip so that shouldn’t be an issue.

A 15A charger will keep up with those loads ... my average leisure battery load in a T6.1 Ocean is about 3A when camped up off-grid. If I turn everything on full, then 10A max on the leisure side. IMO a 25A charger gives a bit more headroom while still being well within the recommended charging current.

My data ...



My solar system is theoretically capable of providing around 25A and even though I have never seen this, it is more than enough to mean I don't need an electrical hook-up for the systems on my van.

 

[Newcs]

Great info. Useful to see the data on the chart as well. Thanks