Running a computer when not on hook up

PMSL!!!!!:lol-049: :lol-049: :lol-049:

bout 20 years ago i forgot to take me leccy razor on holiday..... bought a packet of disposables....aint used a leccy one since.... the cheap supermarket diaposables last me about a fortnight each,
 
bout 20 years ago i forgot to take me leccy razor on holiday..... bought a packet of disposables....aint used a leccy one since.... the cheap supermarket diaposables last me about a fortnight each,

About 35 years ago at an office Christmas drink All the blokes agreed to grow Zapato moustaches over Christmas. I haven't shaved since. :banana: That's 35x365x10 mins extra in bed since.

The pact? Only two of us grew anything, I went for a full beard & one guy had a suberb Zapato. All the others either chickened out or their wives complained!
 
bout 20 years ago i forgot to take me leccy razor on holiday..... bought a packet of disposables....aint used a leccy one since.... the cheap supermarket diaposables last me about a fortnight each,

Use veet :danger: and you'll not have to shave again for several weeks. I use twin blades from wilkinsons. A lot cheaper than branded blades and last just as long.

I don't use an inverter, I try and buy equipment that can run/be charged using the ciggie socket either by usb or directly.
 
We are hopefully upgrading and the van we have seen (and I want) has a solar panel fitted already but Ron wants to know how he can run a computer without being hooked up. Does he need an inverter? or is there a different piece of kit he requires anyone::)

Thank you to everyone who was kind enough to post their comments, Ron says it is OK he is not going to start shaving his legs and he really only wanted it for his computer - it is his other half except he has not married it - but it does go everywhere with us (as long as their is sufficient electricity to use it) and misses it when we go away and don't do hook up.:):cheers:
 
after years of messing about with inverters and with 12 volt chargers that had multisettings and connectors for varying laptops i finally bought a 12v cigarette lighter type charger with a single tip and correct voltage for my laptop ...lasted 5 years without problems ...€12 from ebay germany but no doubt available elsewhere

incidentally , not many people seem to realise that the best way to use a laptop is to only only charge the battery when shut down , then remove the battery and run from the power supply when available ...that's why my battery is as good as new after 5 years , it is rarely used

my solar panels keep the leisure batteries up normally even though running laptop, tv , lights etc
 
Quite right too :) Both my Dells and Alienware laptops allow me to float charge the battery and cycle it even when plugged in.

Anyway you're in a MH or a camper - aren't you meant to be enjoying the outside world, not stuck in front of a laptop for hours on end?! :cool1:
 
Quite right too :) Both my Dells and Alienware laptops allow me to float charge the battery and cycle it even when plugged in.

Anyway you're in a MH or a camper - aren't you meant to be enjoying the outside world, not stuck in front of a laptop for hours on end?! :cool1:

At this time of year it is dark by 7.30, plus, even in summer, I like to download all the day's photos from everyone, edit them & run a slide show for the family. Also good to keep an eye on e-mails too.
 
Any chance of an explanation please?

Technically - 'Float Charge' means keeping the battery at a voltage which keeps it fully charged without gassing or sulphation; 'cycle' means to discharge a battery and then recharge it at a higher 'boost' voltage.

Both of these terms are strictly only relevant to lead-acid (car / leisure) batteries though, and in no way relate to the Lithium-ion batteries fitted to modern laptops I'm afraid. The ability to discharge and recharge the battery was needed for Nickel Cadmium batteries, which suffered a memory effect if not completely discharged before recharge. It's irrelevant to Li-ion batteries, although still existed for a time on laptops because they could be fitted with either battery type.

Three things break Li-Ion cells - age, cycling and over-discharge. Age is impossible to avoid (!), so nothing to be done there. The battery lasts a limited number of cycles, so the more times you flatten it the shorter its life. Over-discharge is prevented by internal circuitry (in the battery itself) but if it's flat and then left without charge for an extended period it will break. If it drops below about 2.7 Volts it can NEVER be recharged because it can cause it to explode. The protection circuitry therefore prevents it charging. Look at youtube for exploding lithium batteries - you won't like it.

So sorry Andy75 and lebesset but actually, it's best to leave a modern laptop battery in the laptop, and plug it in whenever possible. Mine lasted 7 years used like that, and a new one only cost £11 anyway (eBay). And make sure it's fully charged if you intend not to use it for some time. Your advice is correct, but only for now obsolete Ni-Cd and Ni-Mh batteries.

I should qualify - I spent 10 years designing and working on remote solar power installations for critical medical applications, so had to become a bit of a battery expert. Sorry, don't mean to pull rank, but hope I have something to contribute.

Richard.
 
So, does a cycle only count from fully discharged back up to fully charged.

And if you only 1/4 discharge then charge does the logical four of those count as one charge?
 
So, does a cycle only count from fully discharged back up to fully charged.

Technically it's the discharge bit, but no, it's like:

And if you only 1/4 discharge then charge does the logical four of those count as one charge?
This, broadly. So yes, you can have 4 times as many quarter cycles as full cycles. Roughly - it's not quite a straight line as I remember. This also applies to a leisure battery, so keep it on charge where you can.

Richard.
 
Richard, what is your opinion of the so-called leisure and marine batteries (not traction batteries) as opposed to the normal starter and accessory type 12v lead acid batteries?
 
Richard, what is your opinion of the so-called leisure and marine batteries (not traction batteries) as opposed to the normal starter and accessory type 12v lead acid batteries?

Well... It's a bit of a difficult question to answer because there's no real definition of what a leisure battery in particular is. So-called is a good way of describing them.

The theory is that a starter battery has thin plates with lots of area, plus a higher specific gravity (more concentrated) electrolyte, both of which enable it to deliver more current into what is effectively a short-circuit, that is a stalled 2 kW series motor on a cold day (your starter). But both of those also lead to more rapid plate deterioration in cycle life.

A leisure battery should have thicker plates and possibly a lower SG. So it should last longer. There's no real way of checking this, unless you can find a manufacturer who's prepared to give you cycle life data. This looks like: "300 cycles to 80% d.o.d 20h rate" or similar. d.o.d is depth of discharge; 20h rate means that the full discharge takes 20 hours (about right for a motorhome) and cycles is self-explanatory. Actually that'd be a pretty good battery for a motorhome ;-)

My understanding of marine batteries, although I haven't had anything much to do with them, is that they are rated for cyclic use and also engine starting, so a combination of the two.

My opinion is that these types of batteries are a good halfway house. They're not much more expensive than a car battery, if at all, and are likely to give longer service. Of course, there's going to be a difference between the cheapest one on eBay and a proper Lucas or Varta one, but there's a difference in price too. If I was going to live in my motorhome full time I'd opt for deep-cycle or traction batteries; if I thought that age would kill them first I'd opt for leisure batteries.

For example, if the cycle life is 300 cycles, but the life in float service is 10 years (about right for a good one) then you have to nearly fully (80%) discharge the battery 300/10=30 times every year to break it before it wears out anyway. If you only use the motorhome for holidays or mostly use it on hookup that'll never happen, so a leisure battery should be fine.

All that said though, if you regularly discharge the battery to 100% (lights go brown) then any type will struggle to last beyond 10-20 cycles. Same if you fail to fully recharge it, or leave it sitting flat, especially in the cold. Fussy things, lead-acid batteries.

Hope this helps,
Richard.

P.S. There's no second battery in my (recently acquired) Autosleeper! There's a little project to keep me busy - it'll be a leisure battery for me; we don't use it enough for a real one.
 
Pretty much confirms my observations. In some cases I think leisure batteries are simply relabelled starter batteries.

Life seems to be dictated by cycles - but manufactures sell them by guarantee in years.

Some people seem to buy batteries with 4 or 5 year guarantees thinking they must be "good" but I reckon the manufacturer is banking most leisure users will only use them a few weekends a year. If you full time with them and cycle every couple of days, you'll reach 300 cycles within a couple of years and I've found there's not much difference between leisure, marine, or starter batteries. Despite the guarantee and despite the fancy labels they'll all start to fail after this time.

I had some Elecsols with a 5 year guarantee that only lasted 2 years full timing, although I looked after them fairly well. I phoned the company up, but the guy said I obviously hadn't been charging them properly and they would have to be sent back by post for testing by them, to prove they were defective. I couldn't be bothered what with huge posting and packing charges and no guarantee of a result, so just got new batteries. These ones too are now just starting to fail coming up to two years, again full timing.
 
Pretty much confirms my observations. In some cases I think leisure batteries are simply relabelled starter batteries.

Life seems to be dictated by cycles - but manufactures sell them by guarantee in years.

Some people seem to buy batteries with 4 or 5 year guarantees thinking they must be "good" but I reckon the manufacturer is banking most leisure users will only use them a few weekends a year. If you full time with them and cycle every couple of days, you'll reach 300 cycles within a couple of years and I've found there's not much difference between leisure, marine, or starter batteries. Despite the guarantee and despite the fancy labels they'll all start to fail after this time.

I had some Elecsols with a 5 year guarantee that only lasted 2 years full timing, although I looked after them fairly well. I phoned the company up, but the guy said I obviously hadn't been charging them properly and they would have to be sent back by post for testing by them, to prove they were defective. I couldn't be bothered what with huge posting and packing charges and no guarantee of a result, so just got new batteries. These ones too are now just starting to fail coming up to two years, again full timing.

I think that's all spot on, particularly about guarantees. How do you prove you've been charging them correctly? No way I can think of which is practical for a vehicle. Full-timing definitely warrants proper batteries.

Some people say that the most economical way is to cycle to 50%, so size your battery so that it is always discharges that much and no more. If you're regularly cycling to near-flat, then double the size and use the same amount of power / energy. Maybe it works - we used to do that in the solar business, but for lifetime not economy. You can't go much bigger on a solar system for fear of not getting enough charge.
 
I reckon alternator charge can be a pretty blunt sword without B2B or some box of tricks, but for much of my two years I had a 240v smart charger and used this 2 or 3 times a week. I found that seemed to give a much better charge ( I think it has periods of constant current and constant voltage charging). So I had looked after the batteries fairly well.

Also I try not to discharge more than 40 to 50% (11.8v-12v) for the purposes of extending battery life.

This time I am going after 2 x 6V Trojans in series (maybe T105s) to see how they perform. Have 180w solar panels to keep them topped so I'm hoping for 4-5 years life this time. May have to rebuild the battery compartment though!!
 
2x95 Vartas, 9 years old and going well.
A leisure battery is a viable option if they are from a reputable company imo.
 

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