What does "drop in replacement" actually mean when talking about Lithium Batteries?

[Reapr]

Hi,

 

I have a small system just to beat load shedding. A little Mercer 1400W (24V) desktop type inverter.

I got this 2 years ago with some cheap batteries for 200Ah total - all they had to do was power 2 PC's and a router through load shedding, and they did that with roughly 75% left after each power cut.

Well it is now 2 years later and the batteries are done. they barely do 20 mins now, so time for new batteries, but reading here about lithium batteries, leads me to believe they should last longer than the lead acid ones (although at a cost)

Problem is, my little Mercer cannot do Lithium, only Lead-acid, but the S100's for example say that they are "drop in" replacements for lead-acid batteries - does that mean they will work ok on my Mercer, how do they do that?

Doesn't Lithium batteries voltage work differently as they discharge?  Or will the BMS in the battery cut the power?  

Colour me confuse and your help & advice would be appreciated.

Do I go for the Lithiums, or just stick with Lead acid and replace every two years?

Thanks!

 

 

 

EDIT: Ok, seems no one knows, so I'll just buy some more lead acids

 

Edited November 16, 2021 by Reapr
update

[Greglsh]

Hi @Reapr

Check out this forum, a few guys are running the Hubble S100's on the Mecer inverters and they say they should work fine.

 

https://mybroadband.co.za/forum/threads/mecer-2400va-inverter-community-support.1015178/page-382#post-28398042

[zathras]

Hi @Reapr, I've been running a drop in replacement as a load shedding backup for over a year now with no hassles. Mecer 200ah 2nd life lithium. Cheapie ceil inverter sees it as a lead acid battery. Since July, the battery has been connected to an epever mppt solar charge controller, on AGM setting {was close to the upper and lower voltage cutoffs I wanted to use}, so it also sees it as a lead acid battery. Think the BMS in the battery should handle everything for you. In my setup, I've never let the voltage go below 13.1v, so I can't speak to longevity with deep discharge.

[system32]

TIP: On any inverter with Lead batteries remember to set the "Shutdown Voltage" to prevent damaging the battery.
Not sure what the value is for a 24V, but for a 12V it's usually around 11.6V to 12V depending if the measurement is under load or not.


The default on many cheap inverters is 10.5V - yes I'm looking at you Mercer.

 

You will need to lower the value for Lithium which can be discharged to ~20% SoC/80% DoD without damage.
Lithium battery will outlive the inverter.
 

 

[Yellow Measure]

On 2021/11/15 at 11:03 AM, Reapr said:

Hi,

 

I have a small system just to beat load shedding. A little Mercer 1400W (24V) desktop type inverter.

I got this 2 years ago with some cheap batteries for 200Ah total - all they had to do was power 2 PC's and a router through load shedding, and they did that with roughly 75% left after each power cut.

Well it is now 2 years later and the batteries are done. they barely do 20 mins now, so time for new batteries, but reading here about lithium batteries, leads me to believe they should last longer than the lead acid ones (although at a cost)

Problem is, my little Mercer cannot do Lithium, only Lead-acid, but the S100's for example say that they are "drop in" replacements for lead-acid batteries - does that mean they will work ok on my Mercer, how do they do that?

Doesn't Lithium batteries voltage work differently as they discharge?  Or will the BMS in the battery cut the power?  

Colour me confuse and your help & advice would be appreciated.

Do I go for the Lithiums, or just stick with Lead acid and replace every two years?

Thanks!

 

 

 

EDIT: Ok, seems no one knows, so I'll just buy some more lead acids

 

The BMS used inside the S-100s manages all of that. It also ensure that the cells are never charged to 100%, so it avoids shortening the lithium cells' life. Two S-100s work very well with the Mecer 1400W inverter, we have them for our complex's gate motors for a few months now.

[Sc00bs]

14 hours ago, system32 said:

TIP: On any inverter with Lead batteries remember to set the "Shutdown Voltage" to prevent damaging the battery.
Not sure what the value is for a 24V, but for a 12V it's usually around 11.6V to 12V depending if the measurement is under load or not.

One of the main differences between Lead Acid & Lithium is the way that the voltage vs SOC ratio works. 

In Lead Acid batteries it is basically a straight line between 100% charged at 13V and 10% charged at 10.31V. 

Lithium batteries have a much flatter voltage curve between 90% & 10% SOC with the voltage ramping up and down quickly once outside the 10% - 90% range. 

I would check the discharge curve for your specific battery and try to set it as close to the 10%-90% range as possible so as to get the maximum life out of the battery. 

This trait also makes it a lot more difficult for the inverter to accurately tell what the SOC of the battery is as the voltage difference between a 20% SOC & 80% SOC is so small and is one of the reasons why having a communication cable between the inverter and the BMS so as to be able to get an accurate SOC on the battery is preferable. 

Edited December 5, 2021 by Sc00bs

[Mantas]

On 2021/12/05 at 8:30 AM, Yellow Measure said:

The BMS used inside the S-100s manages all of that. It also ensure that the cells are never charged to 100%, so it avoids shortening the lithium cells' life. Two S-100s work very well with the Mecer 1400W inverter, we have them for our complex's gate motors for a few months now.

I know I'm reviving an old thread but with good reason. I have been totally opposed to drop-ins until now because there simply wasn't enough data available as to their reliability, two years ago.

If you are still around, can you please give some feedback as to how your Drop-ins are doing? It's been a couple of years now so if they are still keeping you happy I'll be convinced that drop-ins are viable replacement option for LAs.
 

[Moffat]

My experience with Bluenova BN13V-8-104WH was awful, despite it being touted as a "direct drop-in" for electrical gates with 12v AGM/Gel batteries. You need to ensure that your inverter or charge controller is able to correctly "FULLY CHARGE" the battery. My battery lasted just shy of 6-months and it became swollen and refused to honour the warranty citing the battery being "undercharged" by my UPS. So take caution on under-charging. As for overcharging and cutoff voltage, I am sure the BMS will work but also leave some head-room above the recommended values so BMS doesn't always need to kick in. It's better to be safe than sorry and also lose out on your warranty.

[WAP]

I have 2 x Bluenova BN13V-8-104WH batteries installed in Nov 2021. They have been running without issues.

They operate 2 x double swing gates. Centurion Vector motors. 2 motors per battery. The one battery also supplies power to 4 x G-Speak intercom systems at the one gate. 

I have not found them dead once. Even with prolonged power outages. Just drop in replacement. Did not change any other hardware.

[Mantas]

LOL now see my predicament?! Two very different experiences with the exact same model of batteries.

All the reading I have done over the years, highlights one thing... Lithium is Super sensitive to over charging, which any LA charger is going to be doing. What exactly is the BMS doing with the extra voltage it is getting from the LA charger? Converting it to heat? Magically getting rid of it somehow? Returning it to sender via the SA Post office?

As per my understanding, the BMS is NOT the be all and end all. It is supposed to be a LAST line of defense in protecting your battery from damage from whatever cause. It is not a regulator and should not be used as your first line of defense. All the BMS is going to be doing is outright stopping the charging, which will likely leave your battery under charged. The ones that don't advise you to replace your charger all waffle on about BMS this and BMS that...

So, do these "Direct Drop in" batteries REALLY exist or is it simply a sales gimmick to sell more expensive batteries and then to dispute ANY warranty issue and blame the end user for "Inappropriate usage"?

I have a client, that, despite my recommendation to the contrary, replaced some l-cheapo UPS batteries on their PLC cabinets with these "Direct Drop In" whatnots and they were poked within less that a month.

I think I will still be avoiding them for now...

[Yellow Measure]

3 hours ago, Mantas said:

I know I'm reviving an old thread but with good reason. I have been totally opposed to drop-ins until now because there simply wasn't enough data available as to their reliability, two years ago.

If you are still around, can you please give some feedback as to how your Drop-ins are doing? It's been a couple of years now so if they are still keeping you happy I'll be convinced that drop-ins are viable replacement option for LAs.
 

No issues to my knowledge.

[HelgaR]

There is also the issue of keeping the batteries balanced, most cheap inverters just charge both in series. Check the maximum charge

voltage does not exceed 28.4v at the tail end of the charge cycle. A bad BMS can wreck a battery. I would rather fit a single 24v lipo with the right protection.

[Scorp007]

10 hours ago, Mantas said:

LOL now see my predicament?! Two very different experiences with the exact same model of batteries.

All the reading I have done over the years, highlights one thing... Lithium is Super sensitive to over charging, which any LA charger is going to be doing. What exactly is the BMS doing with the extra voltage it is getting from the LA charger? Converting it to heat? Magically getting rid of it somehow? Returning it to sender via the SA Post office?

As per my understanding, the BMS is NOT the be all and end all. It is supposed to be a LAST line of defense in protecting your battery from damage from whatever cause. It is not a regulator and should not be used as your first line of defense. All the BMS is going to be doing is outright stopping the charging, which will likely leave your battery under charged. The ones that don't advise you to replace your charger all waffle on about BMS this and BMS that...

So, do these "Direct Drop in" batteries REALLY exist or is it simply a sales gimmick to sell more expensive batteries and then to dispute ANY warranty issue and blame the end user for "Inappropriate usage"?

I have a client, that, despite my recommendation to the contrary, replaced some l-cheapo UPS batteries on their PLC cabinets with these "Direct Drop In" whatnots and they were poked within less that a month.

I think I will still be avoiding them for now...

I have 2 sets of drop inn's and yes I have 2 x S-100 and they have never switched off. Wonderful battery. Just like other batteries in series just use a balancer to balance between the 2 or more. The BMS in each one cannot cater for it. 

It is not enough to ensure the 2xseries is at the correct series voltage as one might be lower than the other one while the series voltage is correct. 

I use the HA01/02 balancer. 

This is just like 1 guy has a x inverter and rate it scrap while the next guy has the same and is happy with it.

Edited February 5 by Scorp007

[Nicholas Strachan]

7 hours ago, Scorp007 said:

I have 2 sets of drop inn's and yes I have 2 x S-100 and they have never switched off. Wonderful battery. Just like other batteries in series just use a balancer to balance between the 2 or more. The BMS in each one cannot cater for it. 

It is not enough to ensure the 2xseries is at the correct series voltage as one might be lower than the other one while the series voltage is correct. 

I use the HA01/02 balancer. 

This is just like 1 guy has a x inverter and rate it scrap while the next guy has the same and is happy with it.

I dropped in 2 x s100 into my girlfriends mecer inverter system as the lead acids were stuffed plus I added a balancer and they work a treat.

[Mantas]

13 hours ago, Nicholas Strachan said:

I dropped in 2 x s100 into my girlfriends mecer inverter system as the lead acids were stuffed plus I added a balancer and they work a treat.

Can you give me a link or a model of the balancer? I'd like to check it out.

[Scorp007]

26 minutes ago, Mantas said:

Can you give me a link or a model of the balancer? I'd like to check it out.

If I may chip in. I use this one. 

https://shop.thesunpays.co.za/products/battery-balancer-24v-to-48v-battery-banks

[Spys]

I have a 12v BlueNova “drop in” on my electric fence energizer. It’s been running for 2.5yrs no problems. 
 

I have a 24v Red Pole LifePO4 drop in on my garage door motor. Been about 6 months. No problems. 
 

I have a 12v el cheapo lifepo4 on my Centurion gate slider motor. Been about a year. No problems. 
 

I have another of the 12v el cheapo lifepo4 dropped into my house alarm. About 2 years now. No problems. 
 

All of these were direct swaps with the old LA/Gel batteries. No changes to charges etc. 

[Mantas]

On 2024/02/06 at 9:48 PM, Spys said:

All of these were direct swaps with the old LA/Gel batteries. No changes to charges etc.

This gives me some hope, thanks!

[LeonardF]

I agree with the simple drop in for a 12V alarm system battery especially if the draw on the battery is relatively small.

The problems I see with the two battery trolley setup and using two S-100 lithium ion batteries is that you are paying quite a premium to stay on 12/24V. The S-100s also only showing 3000 cycles compared with 6000 cycles. The popular voltage for lithium ion is 48V and you can get fairly decent 5kwh packs with 6000 cycles for just over R20k.

Two S-100 plus a balancer is gong to cost R13k to 15k. So you have half the capacity (2.5kwh vs 5kwh) and half the cycles for R5k cheaper

 

Then you are still stuck with the biggest problem which is the inverter that cannot take advantage of the fast charging. They are often charging at 10A or 15A where you would want to be charging at 50 to 100A. In stage 4 load shedding the next outage is often 4 hours away. There is a reason those S-100 only have a 2 year warranty 

I would think it may be better to cut your losses and get a 48V battery and a 48V inverter that can charge the battery at 50 to 100A. Unfortunately its going to be R28k plus

[Scorp007]

11 hours ago, LeonardF said:

 The S-100s also only showing 3000 cycles compared with 6000 cycles. 

Then you are still stuck with the biggest problem which is the inverter that cannot take advantage of the fast charging. They are often charging at 10A or 15A There is a reason those S-100 only have a 2 year warranty 

I would think it may be better to cut your losses and get a 48V battery and a 48V inverter that can charge the battery at 50 to 100A. 

I am not aware of a S-100S but only a S-100A with 4000 cycles indicated. The S-100 was sold over 2 yrs ago with 2 life cells while this model uses 1st life cells. 

Have a look at how many problems members are finding with other brands that quote 6000 cycles and don't even make 1000. No names mentioned. 

Edited March 23 by Scorp007

[LeonardF]

11 hours ago, Scorp007 said:

I am not aware of a S-100S but only a S-100A with 4000 cycles indicated. The S-100 was sold over 2 yrs ago with 2 life cells while this model uses 1st life cells. 

Have a look at how many problems members are finding with other brands that quote 6000 cycles and don't even make 1000. No names mentioned. 

Apologies, I was referring to plural with the "s"

 

Point taken on the 6000 cycle cells. This lithium ion game of full of quality an credibility issues

I see the specs are different on the takealot website

https://www.takealot.com/hubble-s-100a-1-2kwh-12v-100ah-lifepo4-first-life-cells/PLID94061368?gad_source=1&gclid=Cj0KCQjw-_mvBhDwARIsAA-Q0Q6zIaIQtdQl_ugJyKqAShuHgALxXwWfUzx05bSRakbHyULgVqxhzuQaAsFhEALw_wcB&gclsrc=aw.ds

With the two battery trolley solutions it may not be a straight forward solution as throw in two S-100A LiFePo4 batteries and a balancer. The point I was trying to make was:

• You are paying a premium for the 12V format vs 48V (Cost per kwh and cycles)
• You are going to have less than ideal charging from the inverters that usually come with these two battery systems. (It may not even work)

Also take a look at the warning on the Geewiz website:

https://www.geewiz.co.za/lithium-ion-batteries/209744-hubble-s-100a-12kwh-12v-100ah-lithium-ion-lifepo4-battery-first-life-cells-used-still-healthy-.html?gad_source=1&gclid=Cj0KCQjw-_mvBhDwARIsAA-Q0Q7Gb7B7hpruRL9z8P67z2imD_k99dqyYFqoY6YI5ajwVPiHNPF7DWcaAvCSEALw_wcB

 

 

[Scorp007]

1 hour ago, LeonardF said:

Apologies, I was referring to plural with the "s"

 

Point taken on the 6000 cycle cells. This lithium ion game of full of quality an credibility issues

I see the specs are different on the takealot website

https://www.takealot.com/hubble-s-100a-1-2kwh-12v-100ah-lifepo4-first-life-cells/PLID94061368?gad_source=1&gclid=Cj0KCQjw-_mvBhDwARIsAA-Q0Q6zIaIQtdQl_ugJyKqAShuHgALxXwWfUzx05bSRakbHyULgVqxhzuQaAsFhEALw_wcB&gclsrc=aw.ds

With the two battery trolley solutions it may not be a straight forward solution as throw in two S-100A LiFePo4 batteries and a balancer. The point I was trying to make was:

• You are paying a premium for the 12V format vs 48V (Cost per kwh and cycles)
• You are going to have less than ideal charging from the inverters that usually come with these two battery systems. (It may not even work)

Also take a look at the warning on the Geewiz website:

https://www.geewiz.co.za/lithium-ion-batteries/209744-hubble-s-100a-12kwh-12v-100ah-lithium-ion-lifepo4-battery-first-life-cells-used-still-healthy-.html?gad_source=1&gclid=Cj0KCQjw-_mvBhDwARIsAA-Q0Q7Gb7B7hpruRL9z8P67z2imD_k99dqyYFqoY6YI5ajwVPiHNPF7DWcaAvCSEALw_wcB

 

 

My spec sheet was from Hubble directly. Too many errors on seller specs. 

Yes timing and deals are important but more so the seller due to a lot of junk and scams. 

When I bought my S-100 with 2nd life I paid R4 400 each including free delivery. At that point in time this was about the cost of 4x100Ah DIY cells only. My basic load test gave me a capacity of 114Ah. After about 2 yrs the same test gave me 110Ah. Both viewed as estimates and only discharged to 11.8V under load. I have never discharged them below 11.5V.

Also in Nov 2021 other including 48V 5 kWh were selling at about R5 500/kWh. Prices are very sweet at the moment for all PV equipment. 

Edited March 23 by Scorp007