OmniPower batteries; very bad and unreliable

[BenBB]

I thought I would add this to the forum as people are being mislead and no one is doing anything about it.

I'm an electronic engineer and have 30+ years experience in electronic design of many types. Specializing in microcontrollers mixed with analogue designs and the like. From concept to final product. 

A couple of years ago I did a solar camera installation for a farmer in Limpopo. Long story short; I used Royal 45Ah and 65Ah lead acids as the battery of choice. Then after 2 years they started failing. They couldn't hold current anymore. The solar is only 140w 7.7A 18v panels. My charger is a self designed circuit based on the LT3790. Capable of delivering all 7.7A of current at 14.7v. I then went to sintech in 2020 (will NEVER use them again) and bought 9 new batteries; they analyzed my design and recommended Omnipower 60Ah 12v Agm/VLR batteries. So I bought them. 6months later they started to fail. Could not even deliver 20Ah (or 1.5A for 14Hrs) I took some back and they accused me of exposing the batteries to high temperatures of 45degrees... WHAT! I took the OPR60 data sheet and showed them that at a constant temp of 60degees C they say the battery must last 2years.. at 25 degrees at leat 10 years!! They therefore did not want to honor the warrentee.. 

I also bought x2 100Ahr batteries and installed that in my garage on a 1500KVA UPS. At a constant temp of around 25degrees in a 19inch rack. They too are now starting to fail. 1 year down the line; Being charged by the UPS and doubled with solar. 

There is a fundimental issue with omnipower batteries. And I think I know what the issue is. Nothing to do with Temperature but all to do with charge current!!

But Sinetech refused to honor the warranty; even when they advised me on the batteries and now DENY EVERYTHING flat out. They never knew my application.. really..

I'm in the process of making a consumer goods council case against them. I bought temperature loggers and logging battery temperatures. I also cut some batteries open to see if the batteries are dried out as this is the tell tale of high heat.. 

I'm also buying a battery analyzer to test the batteries

I believe there is a fundamental flaw in these batteries and if NOT charged in lab conditions will deteriorate Very quickly!! 

So be warned. Omnipower batteries are NOT worth it. Communica also buys them from sintech and I bough one from communica which also started to fail.

I will post my results of the tests as I go along. Even trying some desulfication techniques on the dead batteries NOW 1year old 

 

Edited November 30, 2021 by BenBB
Typo

[isetech]

The 240 amp/hr ominipower batteries we are using failed within 2 years ... we were fortunate they replaced all 4. 

 

[BenBB]

Good for you that they honored that; but there you go Omnipower 240Ah failing after 2 years !! Supposed to have lasted 10years... so be ready to replace them again in 2 years.. they will fail again.. 

[Gnome]

There are quite a few benchmark videos online comparing different brands of Lead Acid batteries.  The only constant among them is that all brands of lead acid suck.  When they tested the most expensive lead acids to least expensive deep cycle, the results are typically that the most expensive batteries don't last much longer.  So don't bother buying these super expensive lead acid batteries, it is good money after bad.

As for a lead acid only lasting a year, well, if you constantly cycled them, I'm not at all surprised.  Lead Acid just doesn't do many cycles unless the depth of drain is very shallow.

Highly recommend you switch over to lithium batteries if you are going to be putting a lot of cycles on the batteries.

[P1000]

14.7V is a bit high for an AGM battery. If you keep them at that voltage for long, they won't last long. Ideally you should have a multiple stage charger, where 14.7V can be used as absorption voltage, but float should not be higher than 13.8V.

[solarman]

Agree. We have 5 sites where the omnipower batteries failed between 8 months and 20 months. All of these sites the batteries were purchased in the sema time frame (could be the same "batch"). Settings were correct as advised by the battery supplier. Some of these were on axpert charger/inverters some were on victron charger/inverters.  I wonder if they didn't have a bad batch or if they moved production to another factory and branded them the same? 

 

[isetech]

The plan is to run them until they die then upgrade to whatever the latest and greatest technology available ... they seem to be handling the load shedding ... but I dont expect to get many years life out of them. 

[Travis]

I had a similar problem, although only 1 failed.

 

I had them setup with 4 x 180ah (Actually 150ah at 10h discharge, 180ah at 100h dischage) units, BMV 702. Insulated from heat and cool. Never discharged beyond 50% DOD (so I used 3.6kwh at the most), mostly 30% DOD.

BMV702 says I drew 422kwh from the batteries over 5 years, so 117 discharges. They should have lasted 2250 charge cycles.

 

Mine are the yellow type batteries and I have 1 that falls to 9V after 1.5kwh has been drawn from the system, so it seems it has a dead cell.

[Don]

On 2021/11/07 at 9:58 PM, Gnome said:

Lead Acid just doesn't do many cycles unless the depth of drain is very shallow.

I had 8 x BSB 250 Ah Solar Batteries. When I got them, I switched to battery power before I had solar panels installed to test them and see what I could get out of them. I woke up the second day with an alarm going off in my battery cupboard. I forgot to switch back to grid. I looked after them and tried to limit the draw down to 20-30% discharge depth. According to the specification sheet, they should have lasted about 8 years. 2 Years later I was lucky if I could get 4-6 hours out of them with a load of 500W. 

It is not just Omnipower batteries. It is lead acid and agm batteries in general. They are not suitable for solar applications, no matter what the spec sheet says. Li-ion is the only way to go in my opinion. 

[Gnome]

5 hours ago, Don said:

It is lead acid and agm batteries in general. They are not suitable for solar applications, no matter what the spec sheet says. Li-ion is the only way to go in my opinion. 

Yep cost isn't useful measure for AGM, in my opinion.  This has been my opinion for years.  Recently a guy did a test comparing lead acids to lithium.  Long story short, lead acid regardless of price is pretty useless.

 

[Don]

3 hours ago, Gnome said:

lead acid regardless of price is pretty useless

Thanks for the video @Gnome. It proves what I have been saying for some time now. Lead acid batteries are great for high discharge rates, over a very short period of time applications , i.e. starting a motor. They have not been designed to deliver power over long periods of time, i.e. solar applications. 

[BenBB]

Hi Guys

Proves my point from all the above replies. Sintech sell batteries not suitable for the application. They give wrong advice to make a sale and then not willing to honour warranty when batteries fail even after looking after them. Batteries are meant to store energy and release it according to a spec sheet. What is the point of a battery data sheet if you cannot use as battery according to its spec. Useless.. You say 14.7v to high.. well its printed in bold on the side of OPR60 batteries. Charge at 8A; 10A recomended. 14.3 to 14.7v cyclic use and 13.8v standby... BUT this differ from the data sheet! Charge at 14.1v.. CC... 

I sacrificed a dead OPR60 battery and cut it open... I was surprised. The plates were pristine.. no damage to the lead grid; Pos and Neg plates; inner membranes were still white and shows no deterioration. 

I went one step further took some dead batteries and topped somenwith distilled water and some with VERY mild sulfuric acid mix.. have some 99.8% acid. Made some 5% mix. Topped some up with that mix

I also drilled some batteries and put screws in the plate connectors.. this way I could access all 6 cells individually. I also charged them individually to 2.35v.. 

I went as far as buying a variable load/battery load tester from Amazon. It ended up that after my above techniques I revived a dead AGM capable of delivering less than 1Ah to 5Ah.. surprisingly these "revived" batteries can deliver extremely high constant current for shorter periods like 20A.. @12v stable. And then suddenly deplete. This correlates to the renewed state of 5Ah compared to the pre dead state of 1Ah.. 

However NOTHING I did so far could revive a dead AGM back to 60Ah !!!! 

I'm trying to get my mind around what happens to the battery chemically when it dies. And why even after "replenishing" electrolite does it still not accept charge even if physically there is no damage to the cells. And none dead.. it tells me that something is amiss with the chemicals inside the battery. I would like to know where Omnipower batteries are made and what their QC is like. They look expensive but is it really AGM?? Or mabe cheaper membranes being used or even the pyrogenic silica mix... 

OmniPower-OPR60-Datasheet-1.pdf

Edited November 30, 2021 by BenBB
Typo

[Nitrious]

The age of lead acid for solar is long over imo, lithium ion and flow batteries are the way to go.

However, having had the same sort of issues you have had, this is what I found, and maybe something for you to look at, hope its helpful.

The US military uses the solution below.

USA website https://www.pulsetech.net/

Local supplier -  https://www.batterypulse.co.za/

 

Edited November 30, 2021 by Nitrious

[Gnome]

Quote

PowerPulse® applies high frequency pulsing cycles (not high voltage pulsing) into batteries that work to continuously dissolve and reduce both the number and size of lead sulphate deposits on battery plates

It would have to be high(er) voltage, else what is it pulsing.  Smells like snake oil.

[GreenMan]

Gnome is so right. I built 2 different versions of these de-sulfators. Put a scope on the output and the pulse and ringing were there as per the magazine articles (Elektor I think and the other maybe was ETI) and their PCB designs. 

Tried circuits on half dozen or so different batteries - AGMs and Flooded. Results ? - nada, niks, nichts, niente, nothing...

Tried that in conjunction with Epsom Salts - also nada. 

if it smells like snake oil and tastes like snake oil then highly likely it is snake oil 

I did not cut any cells opens other than a few SLAs but my guess is that there is sediment on the bottom of flooded lead acids that shorts the plates so that no amount of pulsing (except maybe lightning) will fix it. 

[Nitrious]

its just the state of the lead acid battery market really, they're incredibly unreliable in terms of expected performance and lifetime use.

But, as I said worth a shot, got to be better than sawing batteries open.

I got to the point where I'd buy mine "good" but used at almost scrap value, and exchange as they died, with the scrap value taken into account.

Worked out to around R500 per battery exchange every 6 months - 1 year plus 15 mins travel time.

Personally I'd just dump the lot and get lithium ion until flow batteries drop in price and become more readily available for domestic use.

[Russon]

On the 27th of August 2020 I had 2x Omnipower 240ah batteries installed in my daughters Salon. They failed just after 1.5 years. I’m in the process of sourcing a new supplier. I support what BenBB has stated in his post and what he has gone through is exactly what I faced from Sintech with their reply to the company who installed my system. I’m not going to let this rest and want answers, seems they think money grows on trees.

[Elon]

I am also very disappointed with Omnipower batteries, sold by Sinetech. That AGM is worse than Lithium is not disputed, but you should be able to trust the battery specsheet. My 4x 120Ah failed within 10 months/30 cycles. No issues with the inverter/charger nor the temperature, I dont have PV panels so it only cycles with loadshedding. The settings were exactly as sinetech recommended. 

I was able to get them replaced under warrentee, which I'm thankful for, however the second set is now failing after 8 months. Specsheet claims less than 0.002% of omnipower batteries fail in the field due to manufacturing faults. I doubt it.

[-=sT3V3=-]

We should get a bad suppliers/manufacturers sticky on this forum. My old mans omnipower 240ah batteries lasted 8 or 9 months before failing. Sinetech also uses any petty excuse to void warranty.

[deeBee]

I bought 4x 100Ahr OMNIPOWER OPR120-12 batteries in Feb 2020, which I fitted in a 2 series - 2 parallel configuration for my 24V solar powered inverter running 2 fridges. The power grid in RSA is so bad that this was a necessity. This combination could run my fridges for about 48hrs without charge. I have a mains powered 13A PSU set to 24V4 permanently connected to the batteries to ensure that they don't discharge more than 50% as recommended. The batteries generally don't drop below this level overnight so the system is still Solar powered. Boost is 14V7 and Float charge is 14V4 per battery.

I can only remember two occasions when the batteries DOD went below 50%, probably around 80% due to grid failure and rain. At about Jan 2022 I did a capacity test and measured about 90Ahr for one set and about 60Ahr for the other. Now in Jan 2023 they barely make it through the night which is rather disappointing considering the promised 3000 cycles for a 40% DOD (8-10yr life cycle). Didn't even make a third of the expected lifespan!

What I've learnt, like most of the comments, is that Lead-Acid batteries are terrible. Deep cycle or not, they just don't match their spec-sheet.

Currently saving for a rack mount 24V LifePo4 4.5kWh battery but its a lot of money (±R28k)

The struggle is real ;-)