batteries

[TheBiscuits]

1 hour ago, Mike the Boilerman said:

Sounds like even Victron don't have a proper idiot-proof solution rolled out yet then. 

Oh they do, but it would be cheaper to buy another boat ...

[MtB]

1 minute ago, TheBiscuits said:

Oh they do, but it would be cheaper to buy another boat ...

 

I thought Victron installations was Springwood Haven's stock in trade. 

 

Did the people in the link not buy a Victron system that didn't work, then? 

 

[WotEver]

9 hours ago, Mike the Boilerman said:

 

I thought Victron installations was Springwood Haven's stock in trade. 

 

Did the people in the link not buy a Victron system that didn't work, then? 

 

It was a bit more complex than that but I couldn’t be bothered to try to re-read it all to get my head around it. Kevin at Springwood knows his stuff and there were a couple of instances where he apparently had to ‘go away and think about it’. I’m sure that a chat with him would make the situation far clearer. 

 

Oh, and he kept two LA batteries in the mix to use as an alternator sink. 

[peterboat]

Here is a chart from an ev site I am on for Lithium batteries

The second chart is the most interesting one. In here we see how many charge/discharge cycles the battery cell can handle before reaching the EOL (End-of-Life) – 70 % of the initial battery capacity – in different scenarios.
 

• Cycling from 100 to 0 % we get 500 cycles
• Cycling from 100 to 10 % we get 500 cycles
• Cycling from 100 to 20 % we get 1.000 cycles

• Cycling from 90 to 0 % we get 1.500 cycles
• Cycling from 90 to 10 % we get 1.500 cycles
• Cycling from 90 to 20 % we get 2.000 cycles

• Cycling from 80 to 0 % we get 3.000 cycles
• Cycling from 80 to 10 % we get 3.000 cycles
• Cycling from 80 to 20 % we get 3.500 cycles

• Cycling from 70 to 0 % we get 5.000 cycles
• Cycling from 70 to 10 % we get 5.500 cycles
• Cycling from 70 to 20 % we get 6.000 cycles

[WotEver]

15 minutes ago, peterboat said:

Cycling from 70 to 20 % we get 6.000 cycles

So in that respect they’re the same as LA. Only use 50% capacity for maximum life. 

[Alan de Enfield]

17 minutes ago, peterboat said:

Here is a chart from an ev site I am on for Lithium batteries

The second chart is the most interesting one. In here we see how many charge/discharge cycles the battery cell can handle before reaching the EOL (End-of-Life) – 70 % of the initial battery capacity – in different scenarios.
 

• Cycling from 100 to 0 % we get 500 cycles
• Cycling from 100 to 10 % we get 500 cycles
• Cycling from 100 to 20 % we get 1.000 cycles

• Cycling from 90 to 0 % we get 1.500 cycles
• Cycling from 90 to 10 % we get 1.500 cycles
• Cycling from 90 to 20 % we get 2.000 cycles

• Cycling from 80 to 0 % we get 3.000 cycles
• Cycling from 80 to 10 % we get 3.000 cycles
• Cycling from 80 to 20 % we get 3.500 cycles

• Cycling from 70 to 0 % we get 5.000 cycles
• Cycling from 70 to 10 % we get 5.500 cycles
• Cycling from 70 to 20 % we get 6.000 cycles

Very interesting - is this manufacturers data or has someone been doing tests 'to destruction' ?

Is there a link ?

 

So it looks as if the 80/20 guidance is probably not far out for cost v cycles, (but obviously 70/20 is much, much better)

 

Usable capacity would (to me) appear to be much the same as FLA's, (certainly Trojan types) the only benefit being that you only need run your engine for a couple of hours a day instead of 4 or 5 hours a day.

Edited May 20, 2019 by Alan de Enfield

[dmr]

19 minutes ago, Alan de Enfield said:

Very interesting - is this manufacturers data or has someone been doing tests 'to destruction' ?

Is there a link ?

 

So it looks as if the 80/20 guidance is probably not far out for cost v cycles, (but obviously 70/20 is much, much better)

 

Usable capacity would (to me) appear to be much the same as FLA's, (certainly Trojan types) the only benefit being that you only need run your engine for a couple of hours a day instead of 4 or 5 hours a day.

 

I charge my Trojans (just under 700Ah) from about 50% to about 85% in a couple of hours, certainly not 4 or 5. Only do a full charge once every two weeks, the 14 day moving rule is just perfect for batteries.

 

The water tank lasts about two weeks too, and we get itchy feet after 14 days.

 

................Dave

[Alan de Enfield]

3 minutes ago, dmr said:

I charge my Trojans (just under 700Ah) from about 50% to about 85% in a couple of hours, certainly not 4 or 5.

I think you can do that with any FLA's - its the next 10% that takes the time, then the last 5% takes 'forever'.

[Alan de Enfield]

15 hours ago, robby said:

 

400 AMPH lithium iron battery bank will give you 400AMPS but then they are flat no warning but it does not damage them the only problem is they are expensive has anyone found a good supply yet

I think the information table in a post above shows this to be false.

 

• Cycling from 100 to 0 % we get 500 cycles
• Cycling from 70 to 20 % we get 6.000 cycles

It looks to cause some 'expensive' damage to me.

[Guest]

10 minutes ago, Alan de Enfield said:

I think you can do that with any FLA's - its the next 10% that takes the time, then the last 5% takes 'forever'.

Doesn't it just?

[dmr]

8 minutes ago, Alan de Enfield said:

I think you can do that with any FLA's - its the next 10% that takes the time, then the last 5% takes 'forever'.

The age old wisdom was to run the engine 2 hours every day and 8 hours once per week, this implied working the batteries mostly between about 50 and 80% . For us in winter its more like 2 to 2-1/2 hours every other day, and the big charge every two weeks.

 

................Dave

[Alan de Enfield]

6 minutes ago, dmr said:

The age old wisdom was to run the engine 2 hours every day and 8 hours once per week, this implied working the batteries mostly between about 50 and 80% . For us in winter its more like 2 to 2-1/2 hours every other day, and the big charge every two weeks.

 

................Dave

Indeed it was, but as knowledge has evolved over the last few years it is considered that ANY level of discharge will result in a level of sulphation - keeping batteries at 85% for a couple of weeks will be degrading their capacity.

 

Battery chemistry has also changed - the 'new' calcium based batteries (sealed) seem to me to be very prone to loss of capacity.

 

The ideal is to fully charge immediately after use (as per an engine starter battery) not practical in reality but 95+% SoC should be aimed for.

It is all a balancing g exercise between cost of batteries & cost of fuel & engine wear - there is no correct answer.

 

My Father replaces his batteries every 5-6 months because he cannot be bothered (or forgets - he is in his 90's) to recharge them.

 

Batteries are disposable items.

Edited May 20, 2019 by Alan de Enfield

[dmr]

1 hour ago, Alan de Enfield said:

Indeed it was, but as knowledge has evolved over the last few years it is considered that ANY level of discharge will result in a level of sulphation - keeping batteries at 85% for a couple of weeks will be degrading their capacity.

 

The ideal is to fully charge immediately after use (as per an engine starter battery) not practical in reality but 95+% SoC should be aimed for.

It is all a balancing g exercise between cost of batteries & cost of fuel & engine wear - there is no correct answer.

 

My Father replaces his batteries every 5-6 months because he cannot be bothered (or forgets) to recharge them.

 

Batteries are disposable items.

 

I think this is a forum myth generated over the past few years. Decent batteries can be left without a 100% charge for several days. Sulphation is generally reversible, it just gets increasingly difficult. A good charge at 14.8 or even 15v will get the batteries pretty much back to fully harged, and an equalise every few months will recover a bit more.

 

To be pedantic there is probably a tiny bit of residual sulphation after every discharge but I expect to get 5 years of reasonable capacity out of set of Trojans without doing a full recharge every day.

 

..............Dave

[peterboat]

2 hours ago, Alan de Enfield said:

Very interesting - is this manufacturers data or has someone been doing tests 'to destruction' ?

Is there a link ?

 

So it looks as if the 80/20 guidance is probably not far out for cost v cycles, (but obviously 70/20 is much, much better)

 

Usable capacity would (to me) appear to be much the same as FLA's, (certainly Trojan types) the only benefit being that you only need run your engine for a couple of hours a day instead of 4 or 5 hours a day.

Your wish is my command Battery charging: Full versus Partial - PushEVs

[OldGoat]

All this discussion and fiddling about with unaffordable or fiddly batteries.

 

Fit NiFe batteries  see here:-

https://www.bimblesolar.com/batteries/nifebatteries

 

You don't even need any ballast  in the boat...... 

[peterboat]

7 minutes ago, OldGoat said:

All this discussion and fiddling about with unaffordable or fiddly batteries.

 

Fit NiFe batteries  see here:-

https://www.bimblesolar.com/batteries/nifebatteries

 

You don't even need any ballast  in the boat...... 

Kinel they are expensive!! I have them in my Honda Hybrid and they dont cost that much. I will stick with my LifePo4s I think

[mrsmelly]

18 hours ago, ditchcrawler said:

But I have to drive a couple of hundred miles to get to the boat

 

No you dont, just bin the house. There was a hire boat stopped here last week with two couples onboard, both couples were first time boaters. The youngest of the four was an 83 year old lady.

[Alan de Enfield]

2 hours ago, peterboat said:

Your wish is my command Battery charging: Full versus Partial - PushEVs

Many Thanks.

[blackrose]

20 hours ago, dmr said:

Its sesnsible to compare lithiums with proper lead acids, such as Trojans or full tractions, its not really valid to compare them with cheapo leisures.

 

Trojans will go down to 20% charge and will likely survive if you accidentally go a bit lower, they can handle a fair bit of over-charging and contrary to forum "wisdom" can be left semi discharged for many days and still recover.

 

 

 

I recently replaced my Trojans with another set. I'm really not sure what happened to the originals. Perhaps they were dodgy to start with. Looking at what I'd written on them with marker pen when I pulled them out (12.47v delivered) they should have been ok, but the new set were around 12.65v when delivered so much better. The original set were 5 years old but had a very easy life mostly on float charge with occasional cycling. Perhaps that was the problem or perhaps I had overfilled them? They were completely dead a week after pulling them out -  around 10.5v.

[dmr]

30 minutes ago, blackrose said:

 

I recently replaced my Trojans with another set. I'm really not sure what happened to the originals. Perhaps they were dodgy to start with. Looking at what I'd written on them with marker pen when I pulled them out (12.47v delivered) they should have been ok, but the new set were around 12.65v when delivered so much better. The original set were 5 years old but had a very easy life mostly on float charge with occasional cycling. Perhaps that was the problem or perhaps I had overfilled them? They were completely dead a week after pulling them out -  around 10.5v.

I don't know anything about how batteries behave on float charge, or even if Trojans are suitable for this. The people on this forum who do back up power supplies might know more but I don't think Trojans are the usual choice. I reckon they do need to see 14.8 volts quite often to keep them happy, maybe your charger just stayed in float and never gave them a good voltage.  

 

I don't think over-filling would hurt them, it might even help as I believe acid strength contributes to plate corrosion. Batteries will only have a finite life even if never cycled but I haven't got a clue how long this is. The fact that they went down quickly after removing them must be a clue as to what the failure mode was....any suggestions anyone???? The acid in my old ones was very murky when I removed them.

 

................Dave

[Guest]

4 minutes ago, dmr said:

I don't know anything about how batteries behave on float charge, or even if Trojans are suitable for this. The people on this forum who do back up power supplies might know more but I don't think Trojans are the usual choice. I reckon they do need to see 14.8 volts quite often to keep them happy, maybe your charger just stayed in float and never gave them a good voltage.  

 

I don't think over-filling would hurt them, it might even help as I believe acid strength contributes to plate corrosion. Batteries will only have a finite life even if never cycled but I haven't got a clue how long this is. The fact that they went down quickly after removing them must be a clue as to what the failure mode was....any suggestions anyone???? The acid in my old ones was very murky when I removed them.

 

................Dave

Stratification? Results when they don't get stirred up with a good zap now and again. Forklift trucks with LA batteries used to need an equalizing charge about once a month.

[blackrose]

Yes perhaps a lack of cycling and leaving them on float for too long. I think they got charged up to 14.8v every few weeks and the previous Hi-Fase batteries lasted 10 years on the same charging/float regimen and still held a good charge when I scrapped them due to loss of capacity.

 

Like most flooded batteries there's nothing wrong with leaving Trojans on a float charge, but perhaps they stratify more easily than other batteries?

[WotEver]

2 hours ago, dmr said:

The fact that they went down quickly after removing them must be a clue as to what the failure mode was....any suggestions anyone????

Corrosion resulting in soft shorts. Plus they were probably somewhat sulphated anyway so weren’t holding much charge to start with. 

[OldGoat]

4 hours ago, peterboat said:

Kinel they are expensive!! I have them in my Honda Hybrid and they dont cost that much. I will stick with my LifePo4s I think

!aha! the tricks is to buy them second hand (if you can find them...). Because they are indestructible / difficult to ruin, a used set at a reasonable price can be good value.

I listened to a 'mad professor' some years ago when I was building my boat and bought a trailer load. They're still going strong some 20+ years later.

Folks in foreign lands love them  for domestic wind and solar farms - thus they can be as rare as hen's teeth.

Big ad bulky, though.

 

Bimble sometimes have used ones on sale...    

You have to wait - which, of course, folks don't do nowadays....

 

[cuthound]

8 hours ago, dmr said:

 

I charge my Trojans (just under 700Ah) from about 50% to about 85% in a couple of hours, certainly not 4 or 5. Only do a full charge once every two weeks, the 14 day moving rule is just perfect for batteries.

 

The water tank lasts about two weeks too, and we get itchy feet after 14 days.

 

................Dave

 

Is this because you resticting your showers to make the water tank last 2 weeks? ?

Edited May 20, 2019 by cuthound
To unmangle the effects of autocorrect.