Lead acid v lithium ion home storage

[fizzy]

I have been researching this a bit more for my place in Portugal.

I thought £3000 would buy me a recon forklift battery but met up with a mate last night who had recently bought a new forklift battery. Better price than I though - brand new £2550 plus vat including delivery.
This will provide around 36kw/h max but say 30kw/h in real use.
Anyone know how much an equivalent lithium ion would cost?
From what I can gather around £20,000 which is a huge difference but I can't seem to find any real figures. Considering weight is not a problem I think forklift batteries are the best way to go. They reckon they can last 10 to 20 years when looked after. It is all down to how clever the charger/inverter is to look after the battery and not overcharge or over discharge it.

 

[sako243]

Well a quick search on Google shows a Renogy 12V 200Ah battery (2.4kWh) for just shy of £1k so 4.8kWh for £2k (Inc VAT) so cheaper than your forklift setup.

And that's without even looking too hard.

 

[finyuk2005]

I have been researching this a bit more for my place in Portugal.

I thought £3000 would buy me a recon forklift battery but met up with a mate last night who had recently bought a new forklift battery. Better price than I though - brand new £2550 plus vat including delivery.
This will provide around 36kw/h max but say 30kw/h in real use.
Anyone know how much an equivalent lithium ion would cost?
From what I can gather around £20,000 which is a huge difference but I can't seem to find any real figures. Considering weight is not a problem I think forklift batteries are the best way to go. They reckon they can last 10 to 20 years when looked after. It is all down to how clever the charger/inverter is to look after the battery and not overcharge or over discharge it.

so are you buying 60+kw/h of lead acid batteries for 2.5k?
you need to remember that usable storage from lead acid is 50% at best

 

[hotponyshoes]

I've no idea what end-of-life li-ion batteries are worth but lead acid ones have a decent scrap value.
I would expect li-ion to be worth a few quid as scrap as well but if not you might want to take the potential eol return into account?

I've previously bought "scrap" batteries from the scrap yard after checking them out with a tester. 1000a lorry batteries with 1/3 usable capacity left are fine for living batteries on a horsebox and (usually) with rising scrap prices I get the same amount back for them when I weigh them in again a few years later. The acid also has a decent resale value if you can be bothered to process it out.

If space/weight is not an issue then I would think a load of used lead batteries might be a cheap option although you might have quite a bit of ongoing faffing around to mantain the bank correctly?

 

[fizzy]

From what I can gather around £20,000 which is a huge difference

For not much more money, you could buy a whole car with more capacity than you are considering. 36kWh of Lithium ion battery would deliver 36kWh, too.

There are other things to consider, of course. Round trip efficiency, time and effort with servicing/maintenance, longevity.

NiFe cells may be a better investment in some cases, I suppose. It just depends….

It is for static use!

 

[fizzy]

Well a quick search on Google shows a Renogy 12V 200Ah battery (2.4kWh) for just shy of £1k so 4.8kWh for £2k (Inc VAT) so cheaper than your forklift setup.

And that's without even looking too hard.

The lead acid is around 30kw/h so you would need 12.5 of them which is £12500

 

[fizzy]

so are you buying 60+kw/h of lead acid batteries for 2.5k?
you need to remember that usable storage from lead acid is 50% at best

It is actually 48kw/h but I knew it would have to be de rated. It depends how much you try to pull out at once of course. I think 30kw/h is reasonable in my usage.
Obviously lithium is better - but with a 400 to 1000% price difference is it justifiable where weight isn't a problem? After all forklifts and submarines have coped very well with lead acids for many years.

 

[frank horton]

was looking at this myself and was suprised that the special Lith batt are available via Bangood etc for less than 1/2 price...but with a longish time for transport...
but with the demand for batt's in europe I guess somebody will buy in bulk, with a mark up but no transport worries....
there are several diff types of lith battery avilable but that will require more reading...

 

[fizzy]

was looking at this myself and was suprised that the special Lith batt are available via Bangood etc for less than 1/2 price...but with a longish time for transport...
but with the demand for batt's in europe I guess somebody will buy in bulk, with a mark up but no transport worries....
there are several diff types of lith battery avilable but that will require more reading...

Would you invest so much money in a battery pack from some unknown company though?
I wouldn't. You know where you are with lead acid and if one cell goes down it is easy enough and cheap enough to replace. Also the scrap value is pretty good so you get a lot of the smaller outlay back.

 

[pressbrake1]

I’ve got lead acid
Lithium is very nice but space isn’t at a premium
I’ve just found 12kwh of lead acid (48v)for £1000, real capacity 6kw
6kw real capacity for lith is about 6.5 to 7 to get some longevity
For pylon tech or equivalent probably £3-4k but life could potentially be 3x and most importantly high charge rate which solar produces
But lithium need a bms set up . I’ve also noticed emergency backup are still good old simple reliable pb batteries
In a house with space limits, not wanting potential for vapours and loads of money I’d go Tesla power wall with its thermal management system

 

[reb78]

I wish I had the money to invest in all of this and the understanding of the systems to design and install one. I have masses of shed roof space for the panels and loads of space for the batteries.

 

[finyuk2005]

you do see folk with flooded lead acid forklift type batteries saying they will last for many years with a bit of maintenance, and like you say when space and weight arent any issue, and if you get a good price lead acid is still perfectly useful technology!

 

[GRW]

If you get deep-cycle Lead-Acid packs in 2v cell arrays, then you can get packs with bolt-on terminals and which can be topped up with de-ionised water .

Also means you can check individual 2v cell voltages and Specific Gravity to look after the pack health and mtce.

If you get packs assembled ready into packs inside a tank/container- then you can put the packs on a pallet and ship them in one piece ready to connect.

Off-grid, we've had people get 12-years+ from a pack. The "trick" is how you setup the inverter-chargers to charge and drain the pack to get the best out of it.... plus you need to do your periodic "Equalise" cycles so you stir up the electrolyte to keep it in suspension and minimise sulphation and performance drop-off (& boost SG's).

Note also that proper Industrial Deep-Cycle 2v cells have their Ratings based on a 5-hr discharge... where "Leisure" type Monobloc batteries are rated based on a 20-hr discharge (so the Industrial cells are actually significantly stronger as a much smaller load is used to discharge over 20hr).

(Nominal Pack Volts x Cell AH Rating) / 1000 gives you nominal Pack Kw of storage. Divide by 2 for safe discharge Kw (50% DoD).

 

[fizzy]

If you get deep-cycle Lead-Acid packs in 2v cell arrays, then you can get packs with bolt-on terminals and which can be topped up with de-ionised water .

Also means you can check individual 2v cell voltages and Specific Gravity to look after the pack health and mtce.

If you get packs assembled ready into packs inside a tank/container- then you can put the packs on a pallet and ship them in one piece ready to connect.

Off-grid, we've had people get 12-years+ from a pack. The "trick" is how you setup the inverter-chargers to charge and drain the pack to get the best out of it.... plus you need to do your periodic "Equalise" cycles so you stir up the electrolyte to keep it in suspension and minimise sulphation and performance drop-off (& boost SG's).

Note also that proper Industrial Deep-Cycle 2v cells have their Ratings based on a 5-hr discharge... where "Leisure" type Monobloc batteries are rated based on a 20-hr discharge (so the Industrial cells are actually significantly stronger as a much smaller load is used to discharge over 20hr).

(Nominal Pack Volts x Cell AH Rating) / 1000 gives you nominal Pack Kw of storage. Divide by 2 for safe discharge Kw (50% DoD).

My forklift charger blows air into the cells to stir up the electrolyte. Pretty clever system.
I don't use my forklift a great deal but in the 6 years I have owned it I have never had to top them up.

 

[barracuda816]

I just bought lifepo4 batteries from a reliable supplier at. 3.36kwh for 700 euros with would make 30kwh cost 6250 euros (or around £5450). I know that is nearly 2x the price but the longer life and improved voltage/current curved are in my opinion big positives. looked after they should last well over 10years whilst giving >80% lead acid will degrade much quicker than that at anything more than 20% DOD. Even good quality Rolls batteries will underperform compared to lifepo4 and they are still quite spendy.

What is the use case? I'm guessing for home power to go with solar? how long would you need to go without solar input? I use 5kwh per day using everything normally (ie using electricity to cook, washing machine eat) if I where in your situation I would be looking more at a 48v 280ah battery which would comfortably give 3 days without any solar or Generator input. that battery would cost around the same as your forklift battery and then I would think about adding another in parallel in the future if needed. Also staggers the battery replacement costs in the future (so long as you use a decent management system or a disconnect)

That's just my 2 cents, not a should do or you are doing it wrong comment.

 

[fizzy]

I just bought lifepo4 batteries from a reliable supplier at. 3.36kwh for 700 euros with would make 30kwh cost 6250 euros (or around £5450). I know that is nearly 2x the price but the longer life and improved voltage/current curved are in my opinion big positives. looked after they should last well over 10years whilst giving >80% lead acid will degrade much quicker than that at anything more than 20% DOD. Even good quality Rolls batteries will underperform compared to lifepo4 and they are still quite spendy.

What is the use case? I'm guessing for home power to go with solar? how long would you need to go without solar input? I use 5kwh per day using everything normally (ie using electricity to cook, washing machine eat) if I where in your situation I would be looking more at a 48v 280ah battery which would comfortably give 3 days without any solar or Generator input. that battery would cost around the same as your forklift battery and then I would think about adding another in parallel in the future if needed. Also staggers the battery replacement costs in the future (so long as you use a decent management system or a disconnect)

That's just my 2 cents, not a should do or you are doing it wrong comment.

At only 2x the price lithium batteries are definitely worth considering if they are reliable and good quality.
I may be using the place for Airbnb.
It is a big house with big rooms and gets very hot in summer and chilly in winter so electric usage will be very high. Loads of room to put up solar panels etc. Depending on local planning if needed. I anticipate maybe 30kw per day.

 

[fizzy]

fizzy, submarines need to sink and forklifts need counter-balance weight.

They both need the weight.


pressbrake, do you mean kW or should that be kWh. Those units mean different things- kW is power and kWh is energy.

Weight doesn't matter much it will sit on a concrete floor

 

[pressbrake1]

fizzy, submarines need to sink and forklifts need counter-balance weight.

They both need the weight.


pressbrake, do you mean kW or should that be kWh. Those units mean different things- kW is power and kWh is energy.

You will note it’s a typo, or even lazy typing as I quoted the correct term in the first . sentence and know the difference