Are used lead-acid batteries worth using for a budget solar system?

[TimeMachine]

I'm wondering why you need all that steel to raise the solar panels. Couldn't you have used  4 x L brackets of the appropriate dimensions for each panel?

 

I recommend trying cheap used car batteries rather than buying expensive deep cycle. After doing the math and even knowing deep cycle are better for being run down low it is an option that I think a lot don't consider.

Edited May 17, 2023 by TimeMachine

[Muhendis]

9 hours ago, TimeMachine said:

I recommend trying cheap used car batteries rather than buying expensive deep cycle. After doing the math and even knowing deep cycle are better for being run down low it is an option that I think a lot don't consider.

Cheap used car batteries is a waste of time, money and effort.

A used car battery has been changed out of it's car because it can no longer crank the engine enough to start the car. In other words it is knackered. 

The internals of the car battery are relatively thin lead plates designed to supply high current in short bursts. This is something they do very well. The down side of this is that the plates don't have the capacity to deliver any useful current for a sustained period of time. How often have you left your lights on for a time only to find the battery hasn't got enough left in it to start the car?

A deep cycle battery uses much thicker lead plates which won't have the same cold crank amps as the thinner plates of the car battery but the deep cycle battery with it's thicker lead plates is very good at delivering continuous current for much longer periods.

 

Many proponents of lithium chemistry batteries are of the opinion that the lead acid battery in all it's forms is done for and not worthy of consideration for ESS.

But that is not true. I have just installed a number of lead carbon batteries which, after just a few days, have reversed all the negatives people have of that chemistry. My nice new batteries have already demonstrated one of the manufacturers claims. They have charge acceptance which is four times faster than other similar non-carbon types. This is useful if you have an EV and want to start charging earlier.

Similarly lead carbon batteries can discharge much higher currents in a similar way to super capacitors. I have yet to test that.

Cycle count at DoD of 80%, which for a conventional deep cycle battery would be in the order of 300 'ish is now up to 2,000.

At 30% DoD every day we would be looking at 11.6 years life span.

At the moment there is the caveat of temperature at 25ºC. I am however assured by the manufacturer that this type of battery has a better high temperature characteristic. I am currently waiting for more information on this.

 

The down side is they are hernia inducingly heavy. So not good for anything portable.

For ESS this weight is not a problem because, by definition, they are a stationary power source.

 

The other advantage of the lead carbon battery is cost/kW which comes in at TBH 4,141. Assuming the batteries give 10 years service then we have 

TBH 414/Kw/year. 

[TimeMachine]

14 minutes ago, Muhendis said:

Cheap used car batteries is a waste of time, money and effort.

A used car battery has been changed out of it's car because it can no longer crank the engine enough to start the car. In other words it is knackered. 

The internals of the car battery are relatively thin lead plates designed to supply high current in short bursts. This is something they do very well. The down side of this is that the plates don't have the capacity to deliver any useful current for a sustained period of time. How often have you left your lights on for a time only to find the battery hasn't got enough left in it to start the car?

A deep cycle battery uses much thicker lead plates which won't have the same cold crank amps as the thinner plates of the car battery but the deep cycle battery with it's thicker lead plates is very good at delivering continuous current for much longer periods.

 

Many proponents of lithium chemistry batteries are of the opinion that the lead acid battery in all it's forms is done for and not worthy of consideration for ESS.

But that is not true. I have just installed a number of lead carbon batteries which, after just a few days, have reversed all the negatives people have of that chemistry. My nice new batteries have already demonstrated one of the manufacturers claims. They have charge acceptance which is four times faster than other similar non-carbon types. This is useful if you have an EV and want to start charging earlier.

Similarly lead carbon batteries can discharge much higher currents in a similar way to super capacitors. I have yet to test that.

Cycle count at DoD of 80%, which for a conventional deep cycle battery would be in the order of 300 'ish is now up to 2,000.

At 30% DoD every day we would be looking at 11.6 years life span.

At the moment there is the caveat of temperature at 25ºC. I am however assured by the manufacturer that this type of battery has a better high temperature characteristic. I am currently waiting for more information on this.

 

The down side is they are hernia inducingly heavy. So not good for anything portable.

For ESS this weight is not a problem because, by definition, they are a stationary power source.

 

The other advantage of the lead carbon battery is cost/kW which comes in at TBH 4,141. Assuming the batteries give 10 years service then we have 

TBH 414/Kw/year. 

Of course using a knackered car  battery won't work. A battery tester can let you know it's health including if it can supply the high current demand. The option is too easily dismissed. Healthy normal batteries stacked in parallel can work fine. Again, it's a matter of economics. How much is a 100ah deep cycle battery compared to a tested healthy car battery. Especially if you have access to free batteries. A car mechanic will replace a battery because it can't supply the high cranking amps to start a car yet it will be fine to run lighting and a fan and tv. Sure it wont last as long. I still say give them consideration if the math works out. Not for everyone and every situation but for most diy on a budget it is a valid option. Wether you try or not is up to each individual I guess. I do agree that if you are paying full retail for car batteries for solar that is bad.

 

 

Edited May 18, 2023 by TimeMachine

[Phulublub]

19 minutes ago, Muhendis said:

Cheap used car batteries is a waste of time, money and effort.

A used car battery has been changed out of it's car because it can no longer crank the engine enough to start the car. In other words it is knackered. 

The internals of the car battery are relatively thin lead plates designed to supply high current in short bursts. This is something they do very well. The down side of this is that the plates don't have the capacity to deliver any useful current for a sustained period of time. How often have you left your lights on for a time only to find the battery hasn't got enough left in it to start the car?

A deep cycle battery uses much thicker lead plates which won't have the same cold crank amps as the thinner plates of the car battery but the deep cycle battery with it's thicker lead plates is very good at delivering continuous current for much longer periods.

 

Many proponents of lithium chemistry batteries are of the opinion that the lead acid battery in all it's forms is done for and not worthy of consideration for ESS.

But that is not true. I have just installed a number of lead carbon batteries which, after just a few days, have reversed all the negatives people have of that chemistry. My nice new batteries have already demonstrated one of the manufacturers claims. They have charge acceptance which is four times faster than other similar non-carbon types. This is useful if you have an EV and want to start charging earlier.

Similarly lead carbon batteries can discharge much higher currents in a similar way to super capacitors. I have yet to test that.

Cycle count at DoD of 80%, which for a conventional deep cycle battery would be in the order of 300 'ish is now up to 2,000.

At 30% DoD every day we would be looking at 11.6 years life span.

At the moment there is the caveat of temperature at 25ºC. I am however assured by the manufacturer that this type of battery has a better high temperature characteristic. I am currently waiting for more information on this.

 

The down side is they are hernia inducingly heavy. So not good for anything portable.

For ESS this weight is not a problem because, by definition, they are a stationary power source.

 

The other advantage of the lead carbon battery is cost/kW which comes in at TBH 4,141. Assuming the batteries give 10 years service then we have 

TBH 414/Kw/year. 

And lead is ever so slightly more common than lithium.....

 

PH

[Crossy]

52 minutes ago, Phulublub said:

And lead is ever so slightly more common than lithium.....

 

Lithium makes up about 0.002% of earth's crust, but in geologic terms, it isn't particularly rare. There is also a huge amount in sea water.

 

Meanwhile.

 

Lead makes up only about 0.0013% of the earth's crust (slightly rarer than lithium), but it is easily mined and refined.

 

I agree with @Muhendis, lead-acid isn't dead yet.

 

 

[Crossy]

1 hour ago, TimeMachine said:

Especially if you have access to free batteries.

 

Used lead-acid batteries are far too valuable for recycling to ever be free. 

[TimeMachine]

11 minutes ago, Crossy said:

 

Used lead-acid batteries are far too valuable for recycling to ever be free. 

Do you know what the exchange or recycle amount is?

I've seen tested good batteries on Facebook market place for 500baht. A deep cycle 100ah around 4 or 5000 baht. Worth the savings to try at least on a small system first. If you find it workable, add more.

[Muhendis]

1 hour ago, Crossy said:

 

Used lead-acid batteries are far too valuable for recycling to ever be free. 

Yeah.

I got TBH14,600 scrap value for my old 'uns.

[Crossy]

1 hour ago, TimeMachine said:

Do you know what the exchange or recycle amount is?

I've seen tested good batteries on Facebook market place for 500baht. A deep cycle 100ah around 4 or 5000 baht. Worth the savings to try at least on a small system first. If you find it workable, add more.

 

Offhand no, the Motoring forum would be the place to ask what the core fee would be.

 

500 Baht for a "tested" used battery sounds cheap.

[carlyai]

10 minutes ago, Crossy said:

 

Offhand no, the Motoring forum would be the place to ask what the core fee would be.

 

500 Baht for a "tested" used battery sounds cheap.

Local shop gives B200 for the old car battery when you buy a new one.

Better than keeping the old one.

[n00dle]

On 5/17/2023 at 10:12 PM, TimeMachine said:

I recommend trying cheap used car batteries rather than buying expensive deep cycle. After doing the math and even knowing deep cycle are better for being run down low it is an option that I think a lot don't consider.

Unless you are going lithium, there is little point period. 

Why buy a battery that is only good for half its stated capacity?

[Muhendis]

On 5/18/2023 at 9:21 AM, Crossy said:

Used lead-acid batteries are far too valuable for recycling to ever be free. 

20 B/kg at the moment.

[Crossy]

4 minutes ago, Muhendis said:

20 B/kg at the moment.

 

Is that for raw batteries?

[Muhendis]

On 5/18/2023 at 8:06 AM, Muhendis said:

At the moment there is the caveat of temperature at 25ºC. I am however assured by the manufacturer that this type of battery has a better high temperature characteristic. I am currently waiting for more information on this.

The temperature range is 20 - 30ºC for lead carbon batteries which is pretty much the same as Lithium in it's various chemistries.

[Muhendis]

17 minutes ago, Crossy said:

 

Is that for raw batteries?

That is for any lead acid battery in any state of bashedupness.

Also that is the price in sunny ol' Buriram scrap yard.

Raw batteries you say.

Might try grilling them first next time to see if price is better.

 

Here's an interesting recycling explanation.

https://www.batteryrescue.com.au/news/lead-acid-battery-recycling-process/

Edited May 19, 2023 by Muhendis

[TimeMachine]

On 5/19/2023 at 1:44 PM, n00dle said:

Unless you are going lithium, there is little point period. 

Why buy a battery that is only good for half its stated capacity?

All my laptop and phone lithium batteries have been crap. Good to start with but don't think a teslas battery is much good after a few years. 5 max. It will take time for Teslas sales to slow after this realization.

[TronxII]

1 hour ago, TimeMachine said:

All my laptop and phone lithium batteries have been crap. .

Most likely because they have been repeatedly discharged to 0%  and then charged to 100% again, which damages them irreversibly.

I have Lenovo Laptops with 17 years old batteries which still hold charge for 20min to half hour. But there, you can set discharging and charging thresholds.

[n00dle]

On 5/21/2023 at 9:29 PM, TimeMachine said:

All my laptop and phone lithium batteries have been crap. Good to start with but don't think a teslas battery is much good after a few years. 5 max. It will take time for Teslas sales to slow after this realization.

tesla is not the be all and end all in the the battery world.

There are plenty of comapnys making strides on battery tech for home, mobile and marine use and they are not the bateries you use to power your phone or vape.

 

The choice is yours, but why buy a systrem that has limited cycles AND can only be used at arount 40-50 perent of capacity. 

Edited May 23, 2023 by n00dle

[Seeall]

On 5/21/2023 at 10:58 PM, TronxII said:

Most likely because they have been repeatedly discharged to 0%  and then charged to 100% again, which damages them irreversibly.

I have Lenovo Laptops with 17 years old batteries which still hold charge for 20min to half hour. But there, you can set discharging and charging thresholds.

older stuff seems to been built better, like HDD, back in the day hardly every break, now they mostly do

 

[TimeMachine]

On 5/23/2023 at 10:47 AM, n00dle said:

tesla is not the be all and end all in the the battery world.

There are plenty of comapnys making strides on battery tech for home, mobile and marine use and they are not the bateries you use to power your phone or vape.

 

The choice is yours, but why buy a systrem that has limited cycles AND can only be used at arount 40-50 perent of capacity. 

I've ended up setting up a 10*380 watt panel into a basic hivolt inverter to mainly run ac during the day. No batteries. There is so much to consider when choosing what's good for you and your lifestyle. Many questions need answering. It helps to have technical knowledge to decide rather than rely on a profiteering company. But used lead acid would be my choice on a small system. I wouldn't consider a large reliable battery system in Thailand. Just better off paying high bills rather than a big payback period.