150 amps usable power

[jongood]

I just watched that video.
Towards the end it said that one of the ways to avoid overheating and damaging the alternator is to fit a DC-DC charger which is another name for a B2B.
Vanbitz told me when they fitted my 60amp B2B that even when charging a lithium that was well below 50% DOD the highest amperage they had seen outputted by my 60 amp B2B was 55 amps.
If I was to fit lithiums to my motorhome, based on what Vanbitz told me, I wouldn't envisage any alternator problems.

I think that one has been debunked Phil PhilandMena The big issue with the alternator overheating was in boats with slower running engines in a confined space. Regardless the OP has a B2b anyway.

headlight Imo as long as you dont have to change anything else then its a no brainer to go LifePo4, buy a half decent one and stick the old ones in the back of your garage, if you do decide to change Mh's you can take your new battery(s) with you.

 

[headlight]

If I was to fit lithiums, and I say if lol, would I have any issues with regards to the couple of nights a year I go on EHU to check the 240v side of my van is working, bearing in mind my on-board Sargent charger does not have a lithium profile just lead acid.
This is only 2 nights a year, the rest of the time I am not on EHU and charging is from solar and B2B both of which have lithium charge profiles.

 

[Lenny HB]

Yes it should be fine providing you choose a charging profile where the charging voltage is 14.4 v or less, don't use an AGM setting (14.7v).

 

[headlight]

Yes it should be fine providing you choose a charging profile where the charging voltage is 14.4 v or less, don't use an AGM setting (14.7v).

My Sargent charger doesn't have any settings.
It's just lead acid, 14.2v or 14.4v when charging and 13.6v on float iirc.
I would be hooking up with the batteries fully charged so the lithiums wouldn't be drawing much from the charger.

 

[Lenny HB]

My Sargent charger doesn't have any settings.
It's just lead acid, 14.2v or 14.4v when charging and 13.6v on float iirc.
I would be hooking up with the batteries fully charged so the lithiums wouldn't be drawing much from the charger.

That will be OK.

^{_{Subscribers  do not see these advertisements}}

 

[headlight]

That will be OK.

Bugger, so no reason not to fit lithiums lol.

 

[headlight]

I'm going to blame you when I tell the other half I've changed my mind and we're not not getting lead carbons but lithiums
She doesn't even use a hair dryer as she got her hair cut short when we got the van as I told her she couldn't use one

 

[MichaelT]

I'm going to blame you when I tell the other half I've changed my mind and we're not not getting lead carbons but lithiums
She doesn't even use a hair dryer as she got her hair cut short when we got the van as I told her she couldn't use one

Just tell her she can grow her hair again now and the money saved on haircuts will pay for the batteries

 

[headlight]

Just tell her she can grow her hair again now and the money saved on haircuts will pay for the batteries

That would mean me getting a bigger inverter and that's not happening

 

[Wightman]

Sorry have I misread your first post as you state you have 2x 100a/H batteries and want 150a/H over 3 days so unless your batteries are duff or wired in series (which would mean 24 volts!!) then why will your 200a/H ( with some solar charging) not give you your 150a/H?

^{_{Subscribers  do not see these advertisements}}

 

[MichaelT]

Sorry have I misread your first post as you state you have 2x 100a/H batteries and want 150a/H over 3 days so unless your batteries are duff or wired in series (which would mean 24 volts!!) then why will your 200a/H ( with some solar charging) not give you your 150a/H?

Lead acid only give about 50% of the stated amps as usable before the battery dies. Lithium you can go down to about 10% SOC before the bms cuts in.

 

[Pausim]

My Sargent charger doesn't have any settings.
It's just lead acid, 14.2v or 14.4v when charging and 13.6v on float iirc.
I would be hooking up with the batteries fully charged so the lithiums wouldn't be drawing much from the charger.

That fixed profile would do more damage to an AGM than it would to a LiFePO4 battery if it was the main source of charging. Fortunately it sounds like your B2B is doing most of the work.

 

[headlight]

That fixed profile would do more damage to an AGM than it would to a LiFePO4 battery if it was the main source of charging. Fortunately it sounds like your B2B is doing most of the work.

Correct B2B and solar are the charging inputs, depending on the time of year, bar one weekend a year when I go on hookup just to check that my fridge, heating and hot water 240v systems are working.

 

[Wightman]

Lead acid only give about 50% of the stated amps as usable before the battery dies. Lithium you can go down to about 10% SOC before the bms cuts in.

Thanks for explanation but headlight wasn't originally talking about going lithium!!?

 

[MichaelT]

Thanks for explanation but headlight wasn't originally talking about going lithium!!?

No but you wanted to know why his 200a won't give him 150a?

^{_{Subscribers  do not see these advertisements}}

 

[autorouter]

Lead acid only give about 50% of the stated amps as usable before the battery dies. Lithium you can go down to about 10% SOC before the bms cuts in.

It depends on the battery chemistry. Some lead-acid based batteries, ie Gels, can be taken down to 20% regularly with little ill effect. Some AGMs are similar, and some AGMs are more like the 'flooded' lead-acid batteries that should only be taken to 50%.

 

[headlight]

Thanks for explanation but headlight wasn't originally talking about going lithium!!?

Yes correct, I was originally thinking of installing lead carbon AGM's as I mistakeny thought that they would give me the 150 amps I want.
This thread and speaking to some battery suppliers has shown me that my 2 choices to give me usable150 amps with no charging input are lead carbon gels or lithium.
Now I just need to decide which route to go down

 

[MichaelT]

It depends on the battery chemistry. Some lead-acid based batteries, ie Gels, can be taken down to 20% regularly with little ill effect. Some AGMs are similar, and some AGMs are more like the 'flooded' lead-acid batteries that should only be taken to 50%.

But I was talking about lead acid not gel or AGM as that's what the op has?

 

[Wightman]

No but you wanted to know why his 200a won't give him 150a?

Not really, he's got 200 watt solar with MPPT controller so couldn't see why he would struggle unless batteries are duff. We have similar setup but with 150 watt panel and can last over 3 weeks with plenty of tvs/lights etc running and no EHU

 

[headlight]

Not really, he's got 200 watt solar with MPPT controller so couldn't see why he would struggle unless batteries are duff. We have similar setup but with 150 watt panel and can last over 3 weeks with plenty of tvs/lights etc running and no EHU

In the UK in winter ?

^{_{Subscribers  do not see these advertisements}}

 

[Pablo19]

Lithiums all appear to high.
On their sides they are to wide.
I do not have the space for a third lead acid.

I came across these when I was looking for batteries to fit my space. ~Not available at UK retailers but some sites appear to ship them. Like from here

Link

If you download the datasheet they are 188mm high.

 

[peterc10]

I came across these when I was looking for batteries to fit my space. ~Not available at UK retailers but some sites appear to ship them. Like from here

Link

If you download the datasheet they are 188mm high.

No need to go to Germany. KS Energy have one with the same dimensions in their low profile range, the LP120B model. Last year we bought 2 of these 120Ah LiFePo4 batteries to take the place of the two AGMs we had which were the same size. Been working very well for us ever since.