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Lead Crystal - Are they really as good as their claims?


viceroy
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As is always the case I come across useful information after I have spent money, such is life.

I've recently been reading up about lead crystal batteries, which I suspect I didn't look at purely because at the most basic level, the cost per battery is out of my price bracket.

However, reading up on them it would seem they don't mind high temperatures, or extremely low temps for that matter. They can be overcharged without too much worry of damaging them.

They can be drained down to 0% DOD and they bounce back without any damage, and without affecting the number of cycles they can do, and they charge quicker.

Are they really this good, and is it feasible to have half the number of lead crystal batteries when compared to say Gel batteries because you can easily discharge them twice as deep with no worries of shortening their life

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I have read same, but if they are so good as the information claims, why are not more people using them in solar applications? Just wondering.

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I have had 2 x 150Ah for a few years ... (5?) for my indian UPS (24V pure sine with AVR 1200W - I think - maybe more... name is "Trusty" or something of the kind) for my server and I am EXTREMELY happy.

They were a replacement for the third sets of cheap batteries (although batteries are never cheap) of same size I had since the early days of load shedding: the firs two sets lasted only one year per set and the third I replaced after 2 years). In all cases these cheap batteries lasted ~4hrs when new and I replaced each set when went under the 2 hours mark.

I did not use any type of battery monitoring device and the charger is built into the UPS.

First of all I was astonished that the Lead Crystal lasted >8.5 hours with exactly the same load. Secondly that after a full discharge they last even longer (I went over 9hrs and they still kept server going).

My load: my server has a 750W PS  with 22 disks (11 x 3Tb + 11 x 2Tb) but to that I have connected a SAS expander (900W PS) with 24 x 2Tb disks which I normally shut down shortly afterwards if I know I will not need it again (if I power it on it while on batteries it will trip my ups) and that load shedding will last the full 4.5hrs.

oops: forgot to mention on ups i also have my PC :D

In the 5 years I had the batteries I only had run them to UPS shutdown 5 or 6 times precisely because they last so much longer than any previous set I had before. On the other hand because I have no fear to run them too flat I just don't care to look after them.

My verdict: they costed double anything else I had before but they were money very well spent, I even purchased them for my alarm back up, garage door, gate, etc because I know that when I will need them they will be there for me.

I tried to buy them in China when I imported my solar kit but Betta would not sell for export destination SA.

So I purchased an analogous product by another factory (Oliter): specs say they are almost as good as the Deltec/Betta lead Crystal ... but I don't think so. Still price was 3 x  any other Chinese battery so they must be a little better than usual. Oliter talks of 15 years life with 5 year guarantee (but then I am not going to China to complain if I have a problem) and supplied the high altitude version for Johannesburg (apparently the standard valve is only ok up to 1000m).

I have very little clue of what parameters I should use for my hybrid inverter + Oliter batteries but I will find out next week at the Solar Show when I meet my contact at Oliter.

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I have just had the time to watch Martin's video with test results and I am glad to see that are perfectly in line with my practical experience.

In practice: since it is possible to discharge a Lead Crystal battery all the way down you get double the watt hours of a standard lead acid battery and it is almost as if you are comparing one battery (Lead Crystal - 9hours capacity consistently) vs 2 batteries (Lead Acid - each 4 hours capacity when new). But at the end of that you still have your  Lead Acid battery performing reasonably (in fact for me it performs better after a full discharge) while the 2 Lead Acid batteries are shot.

In my mind Lead Crystal is well worth the extra cost.

It would be interesting to compare a 70Ah Lead Crystal vs 2x 70Ah Lead Acid batteries in parallel and see what comes out of this.

 

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On 3/10/2016 at 1:23 PM, The Terrible Triplett said:

I have read same, but if they are so good as the information claims, why are not more people using them in solar applications? Just wondering.

For some reason not as many people use them in their solar applications in SA. Here in Namibia they are installed in quite a few installations and have been performing well.

In the SA market, as well as the European market, they are quite popular in the telecomms industry where the go to battery is the 12V 170Ah Front Terminal.

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14 hours ago, Manie said:

They are expensive. Over R8000 for a 200 ah battery

Sent from my SM-G920F using Tapatalk

They may seem expensive, but if you consider this.

You'll pay around half that for 200Ah GEL AGM batteries. These you'll only discharge to about 70% SOC occassionally going down as far as 50%

With the lead crystal batteries, you will take them as low as 50% without batting an eyelid and can push them much further on a regular basis without worry of damaging them or shortening their lives.

Basically of the 200Ah in the gel battery, you will use 40 - 60Ah regularly and being capped at 100ah.

With the 200Ah in the lead crystal, you will use 100Ah regularly and even go as far as 160Ah.

In my mind, worth the extra cost, or you could buy 100Ah batteries. I did see them below R4000 the other day, but cant find the link :(

The link

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On 3/15/2016 at 0:40 AM, Manie said:

On bid or buy it is R8320 for 200ah deltec

Sent from my SM-G920F using Tapatalk

:o I'm a bit shocked by that price tag!!

On 3/16/2016 at 0:58 PM, viceroy said:

They may seem expensive, but if you consider this.

You'll pay around half that for 200Ah GEL AGM batteries. These you'll only discharge to about 70% SOC occassionally going down as far as 50%

With the lead crystal batteries, you will take them as low as 50% without batting an eyelid and can push them much further on a regular basis without worry of damaging them or shortening their lives.

Basically of the 200Ah in the gel battery, you will use 40 - 60Ah regularly and being capped at 100ah.

With the 200Ah in the lead crystal, you will use 100Ah regularly and even go as far as 160Ah.

In my mind, worth the extra cost, or you could buy 100Ah batteries. I did see them below R4000 the other day, but cant find the link :(

The link

Very good point viceroy! Many people/customers do not take the usable amount of energy available into account when deciding on batteries. Price plays the biggest deciding factor and I guess it will for a long time unfortunately...

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All that bothers me, is that per kwh they just don't seem to match my benchmrk battery (Trojan T105RE). For example, I see that the price for a 200Ah 2V Betta Battery (BC-CNFJ-200, http://www.sustainable.co.za/betta-bc-cnfj-200-200ah-2v-lead-crystal-battery.html) is around R1700 per cell. Yes, I looked in a few other places as well, I know sustainable is at least 15% to 20% more expensive. The datasheet says its good for 3000 cycles down to 50%. Now that is almost double what the Trojan will do. However, the old back-of-the-envelope calculation:

2*200*0.5*3000/1000 = 600kwh over its lifetime

1700/600 = R 2.83.

The Trojan still wins at around R2.30.

I need to get that battery at R1400 before it starts to make sense.

 

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On 3/18/2016 at 3:01 PM, plonkster said:

All that bothers me, is that per kwh they just don't seem to match my benchmrk battery (Trojan T105RE). For example, I see that the price for a 200Ah 2V Betta Battery (BC-CNFJ-200, http://www.sustainable.co.za/betta-bc-cnfj-200-200ah-2v-lead-crystal-battery.html) is around R1700 per cell. Yes, I looked in a few other places as well, I know sustainable is at least 15% to 20% more expensive. The datasheet says its good for 3000 cycles down to 50%. Now that is almost double what the Trojan will do. However, the old back-of-the-envelope calculation:

2*200*0.5*3000/1000 = 600kwh over its lifetime

1700/600 = R 2.83.

The Trojan still wins at around R2.30.

I need to get that battery at R1400 before it starts to make sense.

 

At that price it definitely does not make that much sense! With that said though, I can assure you I do not pay that much for a bank LCB's.

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  • 3 weeks later...
On 3/18/2016 at 3:01 PM, plonkster said:

All that bothers me, is that per kwh they just don't seem to match my benchmrk battery (Trojan T105RE). For example, I see that the price for a 200Ah 2V Betta Battery (BC-CNFJ-200, http://www.sustainable.co.za/betta-bc-cnfj-200-200ah-2v-lead-crystal-battery.html) is around R1700 per cell. Yes, I looked in a few other places as well, I know sustainable is at least 15% to 20% more expensive. The datasheet says its good for 3000 cycles down to 50%. Now that is almost double what the Trojan will do. However, the old back-of-the-envelope calculation:

2*200*0.5*3000/1000 = 600kwh over its lifetime

1700/600 = R 2.83.

The Trojan still wins at around R2.30.

I need to get that battery at R1400 before it starts to make sense.

 

You should need to use a "50% DOD rule of thumb" for the lead crystal batteries to calculate R/Kwh

i.e. using this website's prices as baseline, and comparing the following two batteries:

 

Betta BC-CNFJ-200 200Ah 2V Lead Crystal Battery: 2V, 200A @ R1,727.00. - 48V bank = R41,376

2*200*3000/1000 = 1200Kwh -> 1727/1200 = R1.44/Kwh
2*200*0.7*3000/1000 = 840Kwh -> 1727/840 = R2.05/Kwh
2*200*0.6*3000/1000 = 720Kwh -> 1727/720 = R2.39/Kwh

Trojan T105 225Ah 6V Deep Cycle Battery: 6v, 225Ah @ R2,664.00 - 48V bank = R42,624 (you need two sets for 50% DOD)

6*225*0.5*1600/1000 = 1080Kwh -> 2664/1080 = R2.47/Kwh. 

 

This is asuming the Lead crystal will be drained to 0% on every cycle, and the Trojan to 50% on every cycle. At 30% DOD it's still cheaper than the Trojan, in this example. 

 

IMO lead crystals seem like the preferred option to use, but they are flooded cell batteries and will require much more maintenance than sealed AGM batteries (not tested in this example).

 

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I see. I did the math at different DoD values for lead acids and found that there is very little difference in the final price. I never did the math for lead crystal. My bad, thanks for pointing it out.

I see you also get confused between DoD and SoC :-) You said 30% DoD, but your calculation shows 70% DoD. I think you meant 30% SoC :-)

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Hang on...

6500 cycles to 20%

3000 cycles to 50%

2000 cycles at 70%

700 cycles at 100%

Lifecycle kwh calculation

(2*200*700)/1000 = 280kwh => R6.17

(2*200*0.7*2000)/1000 = 560kwh => R3.08

(2*200*0.5*3000)/1000 = 600kwh => R2.88

(2*200*0.2*6500)/1000 = 520kwh => R3.32

Unless my calculations are wrong, 50% is still the best DoD, and the Trojan still beats the pants off this.

Cycle life charts from here. It's a 12V 200Ah battery, but curves should be similar.

http://offgriddiy.co.za/upload/Lead%20Crystal%20Battery%206-CNFJ-200.pdf

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3 hours ago, plonkster said:

Hang on...

6500 cycles to 20%

3000 cycles to 50%

2000 cycles at 70%

700 cycles at 100%

Lifecycle kwh calculation

(2*200*700)/1000 = 280kwh => R6.17

(2*200*0.7*2000)/1000 = 560kwh => R3.08

(2*200*0.5*3000)/1000 = 600kwh => R2.88

(2*200*0.2*6500)/1000 = 520kwh => R3.32

Unless my calculations are wrong, 50% is still the best DoD, and the Trojan still beats the pants off this.

Cycle life charts from here. It's a 12V 200Ah battery, but curves should be similar.

http://offgriddiy.co.za/upload/Lead%20Crystal%20Battery%206-CNFJ-200.pdf

You just calculated a 2V battery's Kwh using a 12V battery as reference...

With your figures, it should look like this:

(12*200*700)/1000 = 1680kwh => R4.59

(12*200*0.7*2000)/1000 = 3360kwh => R2.29

(12*200*0.5*3000)/1000 = 3600kwh => R2.15

(12*200*0.2*6500)/1000 = 3120kwh => R2.47

 

So, yes, you're right 50%DOD is still the most economical and ideally you should then still get 2x the capacity. With these specific batteries, a 48V bank will cost R30,907.68 or R61,815.36 if you work on 50% DOD values. And then they should last 8.2 years @ 50%DOD. 

 

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Man... I used the cycle numbers from the 12v sheet. That should be similar to the 2v cells, because really, a 12v battery is just 6 cells in one container. It doesn't matter if you use the kWh numbers and price for the whole pack or for just one battery, the answers are the same.

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14 hours ago, plonkster said:

Man... I used the cycle numbers from the 12v sheet. That should be similar to the 2v cells, because really, a 12v battery is just 6 cells in one container. It doesn't matter if you use the kWh numbers and price for the whole pack or for just one battery, the answers are the same.

How can the answers be the same if you use 2V instead of 12V for the calculation? The Kilowatt per Hour will be different. 

2V * 200A * 3500 cycles /= 12V * 200A * 3500 cycles. 

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Just now, SilverNodashi said:

How can the answers be the same if you use 2V instead of 12V for the calculation

Because the kwh goes up, but so does the cost of the battery (because you have 6 cells, not just 1). All things being equal, you just multiplied the entire equation by 6. The final division sum should work out about the same.

For my calculations, I used the price and voltage of the 2V cell, but I used the cycle numbers from the 12V sheet. Unless the 2V cell has a different cycle to the 12V battery (made up of 2V cells not unlike the one in question), my calculations should be sound.

Of course, all other things are NOT equal. The 12V battery might well work out a bit cheaper than 6 x 2V cells of the same capacity, simply because it's more popular, uses slightly less material, or whatever, but I don't expect that will move the price per kwh by more than a few cents.

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11 minutes ago, plonkster said:

Of course, all other things are NOT equal. The 12V battery might well work out a bit cheaper than 6 x 2V cells of the same capacity, simply because it's more popular, uses slightly less material, or whatever, but I don't expect that will move the price per kwh by more than a few cents.

Chance are that the 2v battery has a LOT more cycles in them than a 12v battery.

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Just now, The Terrible Triplett said:

Chance are that the 2v battery has a LOT more cycles in them than a 12v battery.

Not in this case. I remember that the LCs were 3000 at 50% DoD. I remember it, because I remember that it was roughly twice what you get out of a Trojan, and I know by heart (by now) that the Trojan is 1600 at 50%. The curves for the 12V Lead Acid looks exactly the same as the ones for the 2V cell.

In any case, my argument here was that for the LC to make sense in terms of cost, it has to cost less than double the cost of the Trojan per Ah. It doesn't. Therefore, end of story. The Trojan still wins. Not that I want it to. It's bloddy terrible that the messy acid-bucket wins. I also have it on some authority that we're somewhat screwed over in SA. LCs shouldn't cost as much as they do...

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