Li Ion leisure battery

fisherman

fisherman

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Anyone embraced the technonlogy yet?
Daughter's campervan comes on, but not apace. We have gone round and round the battery question. Lead acid, inefficient, minimum useable power, gassing (she works online, so laptop at 4amps or so all day) but ease of fit with VSR split charging, solar and occasional hookup all through one management device.
AGM, different charging regime so more complex, bit more expensive.
Li ion, £lots, maybe £750 cheapest, with unresolved as yet questions about safe charging and possible fire risk, some come with 'built in' charge limitation.

Some stock VSRs won't manage battery banks of differing chemistry.

Can't do Adverc, as I suspected they don't advise a fit in a modern electronically managed vehicle, but they will supply a useful VSR that does a good job and includes emergency start backup button.

At the moment she is leaning towards li ion, but that was ten minutes ago.............
 
fisherman said:
Anyone embraced the technonlogy yet?
Click to expand...

Last time I looked, a year or two back, good quality Li-ion batteries (reputable maker, full monitoring and control systems built in) were about £20 per Ah, while lead-acid was about £1 per Ah. Since lead-acid can only be safely discharged half way and Li-ion can run down completely, that means that Li-ion cost about ten times as much per usable Ah. I've had a quick look, and prices have come down a bit, so the difference is now about 8x (effective), which is still too much for me. At 4x (ie when I can fit 120Ah Li-ion for £1,000 I'll be very tempted.
 
Interesting point about 'electronically managed vehicles'.
My 10 year old car has a clever alternator and fiddles with the charging voltage.
I suspect that using a simple VSR to charge another large battery would not go well.

There are a lot of 12V Li-Ion batteries available for motorbikes.
Many are labelled with the Ah rating of the Lead acid battery they are intended to replace, because it's all about starter current. The true Ah rating is in the small print and is half or a third.
I was still tempted, but the maths of being an early adopter don't do it for me, and I'm not racing so not too bothered about saving a few kg. I don't think the Italian regualtor is great for Lead Acid, god knows what Litihium would make of it....
 
lw395 said:
There are a lot of 12V Li-Ion batteries available for motorbikes.
Many are labelled with the Ah rating of the Lead acid battery they are intended to replace, because it's all about starter current. The true Ah rating is in the small print and is half or a third.
I was still tempted, but the maths of being an early adopter don't do it for me, and I'm not racing so not too bothered about saving a few kg. I don't think the Italian regualtor is great for Lead Acid, god knows what Litihium would make of it....
Click to expand...

My understanding is that Li-ion batteries, being made up of a large number of AA-ish sized cells, need very careful management. Otherwise you can end up discharging the same ones time after time, and they have fairly limited lives, typically 500 - 1,000 full cycles. It's a bit like SSDs, which are careful to share writes across as much of the memory as possible.
 
fisherman said:
Anyone embraced the technonlogy yet?
Daughter's campervan comes on, but not apace. We have gone round and round the battery question. Lead acid, inefficient, minimum useable power, gassing (she works online, so laptop at 4amps or so all day) but ease of fit with VSR split charging, solar and occasional hookup all through one management device.
AGM, different charging regime so more complex, bit more expensive.
Li ion, £lots, maybe £750 cheapest, with unresolved as yet questions about safe charging and possible fire risk, some come with 'built in' charge limitation.

Some stock VSRs won't manage battery banks of differing chemistry.

Can't do Adverc, as I suspected they don't advise a fit in a modern electronically managed vehicle, but they will supply a useful VSR that does a good job and includes emergency start backup button.

At the moment she is leaning towards li ion, but that was ten minutes ago.............
Click to expand...

I don't think anything much has changed since you last asked the question about a month ago. Li-ion batteries (in which category I include LiFePO4) are still eye-wateringly expensive. It would be much cheaper for her to install several decent AGM batteries, which can be charged via a VSR from the vehicle's alternator, as well as separately by solar. No problems with the charging regime - people routinely put AGM batteries into cars. With a modern vehicle, the alternator should deliver a decent voltage so there's no point at all in adding an Adverc or any other alternator booster.
 
fisherman said:
Anyone embraced the technonlogy yet?
Daughter's campervan comes on, but not apace. We have gone round and round the battery question. Lead acid, inefficient, minimum useable power, gassing (she works online, so laptop at 4amps or so all day) but ease of fit with VSR split charging, solar and occasional hookup all through one management device.
AGM, different charging regime so more complex, bit more expensive.
Li ion, £lots, maybe £750 cheapest, with unresolved as yet questions about safe charging and possible fire risk, some come with 'built in' charge limitation.

Some stock VSRs won't manage battery banks of differing chemistry.

Can't do Adverc, as I suspected they don't advise a fit in a modern electronically managed vehicle, but they will supply a useful VSR that does a good job and includes emergency start backup button.

At the moment she is leaning towards li ion, but that was ten minutes ago.............
Click to expand...

Forget batteries and install a small ,generator. It means hot water showers / toaster etc all without having to use batteries or fire up the van engine.
 
There may be better (=more expensive) out there, but the small generators I've seen all make more noise than a main engine. I reckon you still need batteries. Personally, I'd go for deep cycle jobs like Trojans and add solar panels for on-site charging. Ideally, assuming 5 amps for 16 hrs and an amp for 8 hours, you'd want about 400W of panels, but I reckon you'd get away with 200 w in summer
 
JumbleDuck said:
My understanding is that Li-ion batteries, being made up of a large number of AA-ish sized cells, need very careful management. Otherwise you can end up discharging the same ones time after time, and they have fairly limited lives, typically 500 - 1,000 full cycles.
Click to expand...

The Lithium-ion cells you might find in a set of kitchen scales indeed have relatively modest cycle life. However, assuming we're actually talking about LiFePO4 batteries, the only sort that's made significant incursion into marine batteries, their life ranges from something like 2000 to over 6000 cycles (to 80% discharge). LiFePO are more long-lasting than most other types of Lithium battery, at a cost in energy density too modest to be an issue on boats. The do need correctly tailored charge regimes but are not made up in the "multi-AA" way you describe, but as modules more akin in size to those in lead-acid cells.

LiFePOs contain little inherently hazardous material compared to other batteries with similar uses and their main constituent, iron, is plentiful and cheap. As regards fire risk, it often seems forgotten in these debates that the 'baseline' is far from zero, since lead-acid batteries are themselves not entirely safe. LiFePo are anyway far safer than other lithium-based alternatives, particularly during charging. Additionally, they have a very much higher ignition temperature, lower burn rate and much lower burn temperature.
 
The trick to charging LiFePO4 or even Lead Acid correctly is to use a purpose designed alternator controller. A standard "14.2 volts, all day, every day" controller is not the way to go.

I may try LiFe PO4, but probably not by the conventional route. My business partner has about 500Ah of Li, by building up batteries from discarded electric vehicle packs. It runs his entire home, from solar, with enough capacity to cope if the next day is dark or cloudy etc. It need not cost the earth, but you do need to be prepared to get your hands dirty and shop around.
 
macd said:
The Lithium-ion cells you might find in a set of kitchen scales indeed have relatively modest cycle life. However, assuming we're actually talking about LiFePO4 batteries, the only sort that's made significant incursion into marine batteries, their life ranges from something like 2000 to over 6000 cycles (to 80% discharge). LiFePO are more long-lasting than most other types of Lithium battery, at a cost in energy density too modest to be an issue on boats. The do need correctly tailored charge regimes but are not made up in the "multi-AA" way you describe, but as modules more akin in size to those in lead-acid cells.
Click to expand...

Many thanks for that. I mistakenly thought marine batteries were made like the Tesla Powerwalls, which are only good for 500 - 1000 full cycles.
 
More correctly, lithium iron, as I only just realised. Got a local supplier offering 68ah, with mains charger and bluetooth monitor, under £700. They seem to be mostly that price per ah.
 
fisherman said:
Anyone embraced the technonlogy yet?
Daughter's campervan comes on, but not apace. We have gone round and round the battery question. Lead acid, inefficient, minimum useable power, gassing (she works online, so laptop at 4amps or so all day) but ease of fit with VSR split charging, solar and occasional hookup all through one management device.
AGM, different charging regime so more complex, bit more expensive.
Li ion, £lots, maybe £750 cheapest, with unresolved as yet questions about safe charging and possible fire risk, some come with 'built in' charge limitation.

Some stock VSRs won't manage battery banks of differing chemistry.

Can't do Adverc, as I suspected they don't advise a fit in a modern electronically managed vehicle, but they will supply a useful VSR that does a good job and includes emergency start backup button.

At the moment she is leaning towards li ion, but that was ten minutes ago.............
Click to expand...

Why would the battery be gassing ?

She has a very big laptop if it uses 4a all day, mine doesn't.

What campervan does she have ?
 
Lead acid batteries can gas in charge.
The laptop in use and charging uses 2.9A at 20 v, tested with meter, so about 4A at 12v, give or take, including any loss for stepup volts.
Renault Master.
 
fisherman said:
Lead acid batteries can gas in charge.
The laptop in use and charging uses 2.9A at 20 v, tested with meter, so about 4A at 12v, give or take, including any loss for stepup volts.
Renault Master.
Click to expand...

If the domestic battery in a campervan is gassing, you have a problem, they won't noticably gas under normal charging.

The laptop won't always be charging. As i sit here typing this my laptop is using 0.7a, the battery is charged.

Late model Renaults are fitted with smart alternators, if that's the case, you cannot use a VSR,
 
My 27 footer has two lead acid batteries as the house bank (slightly different capacities and different makes which I know is not ideal, approx 80Ah usable capacity).

I'll only upgrade when I have a longer trip in mind. Until then I bring Li ion power banks on board which add an extra 25-50% capacity in a very cost effective way. These handle charging phones, tablets etc, whilst the house bank looks after the installed load.

Examples of these power banks here
https://www.amazon.co.uk/RAVPower-2..._FMwebp_QL65&keywords=li+ion+power+bank&psc=1

No they aren't marinised, but they do live in a dry house for most of the time, and are comparatively cheap, small and replaceable.

4A continuous consumption for a laptop seems high. That sounds more like a peak figure (4A X 12v ~ 50W).
 
there is so much bs about, she spoke to someone today who assured her that his li irons, more expoensive than any other, are the only ones made to standard, all the others will be withdrawn from the market soon, they are made in China and all burst into flames.....she doesn't trust him.

the VSR, or whatever will be in a b to b system, not interrupting the supply from the alternator. Van is 2005.
 
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