ROYAL Big Bang

[Jaco De Jongh]

Good Morning 

I was working on my PC this morning when I heared a shot go off in the house (I was convinced a firearm was involved), but the thing  is, I don't have any..
So after a few seconds of thinking I thought the only other thing that could make that kind of noise is my Inverters...  but the power is still on... so it cant be my inverters, can it?

Went to the inverter/battery room and when i entered i could not breath from all the gasses and the smell told my its got something to do with a battery. Gave it some time to extract the gasses and guess what i found......

 

 

This is a second hand Royal I bought from someone on this forum to test an Idea I had to keep all my 12 volt equipment like routers , switches ext going during a power failure. It was kept in a charged state with only 2 discharges in about a year. Charged by a 75/15 Blue MPPT. It was just over a year old when i bought it. In hindsight, I should have replaced him with a more reliable battery when i saw the plan worked, but never got round to it.

No I must go clean up the rest of the equipment in the room.. what a mess!!!

Please comment on possible reasons?

[Johandup]

Normal batteries give of hydrogen which is far more flammable than methane (I'm a retired coal miner) and is also very light in weight.

It would thus form a layer against the ceiling where any spark can ignite it.

It would be a good idea to have a vent for such gas in the highest position.

A roof fan is definitely not a good idea.

If you are close to a colliery you can look at their lamp room layouts.

Sorry about the damage - remember to use an acid neutraliser and protective gloves.

[Mako]

That looks like an internal battery fault that ignited the hydrogen inside that battery. If it was build up at the ceiling the ceiling would be gone.

 

[Jaco De Jongh]

15 minutes ago, Johandup said:

It would be a good idea to have a vent for such gas in the highest position.

Hi Johan, that fan was a 12volt dc test fan for a client, hanged it there for a test, but he wasnt happy with the results so I just left it there. Just out of view on the picture is 2 x 12 volt extractor fans to get rid of the gasses. 

12 minutes ago, Mako said:

internal battery fault

I suspected the same, but Im no expert on batteries.. 

[___]

TTT had one blow up in a ups too. 

[Chris Hobson]

I once had a vented battery do a similar thing. Someone who I thought was responsible had been delegated (by my father)  to check and top up electrolyte for a bank of batteries. When I came to the farm I saw no need to change anything. Unfortunately said deployee was less than routine in his battery maintenance.  A battery exploded in spite of being vented and my conclusion on inspecting the other two batteries was that electrolyte levels were very low. From that day I have taken personal responsibility for the maintenance of all batteries on the farm.

[Johandup]

I used to run battery haulers on the mine with huge batteries and had to deal with all the issues.

Ventilation was supplied by a 37kW fan for cooling and gas dilution - we also had an electronic detection system for ventilation speed and gas concentrations.

We had an automatic level system for the filling of the cells - interestingly we had a machine to make our own battery water as we used a lot.

I remember the weight was 5 tonnes per battery but cannot remember the number of cells - we had permanent battery attendants 24/7 doing the maintenance and the data recording.

The one section till today holds the record production of 161 500 tons coal for a board and pillar section running three battery haulers and one continuous miner.

It is amazing to look at the damage surrounding the battery in the area in the photo when you calculate the minute volume of hydrogen in a battery's cavities.

Btw, you need special flameproof equipment when dealing with electric equipment that comes into contact with flammable gases.

Here is a point to ponder: When hydrogen is inhaled and then ignited it will burn into your lungs.

(I tried to copy and paste from my MacBook Pro but it does not do it in High Sierra)

 

[GVC]

That is bad luck Jaco, it reminds me of how much extra care we have to take with our systems.

I am by no means an expert on batteries, but do you not think the current heatwave we are experiencing had a contribution? It reached 34°C in our area today, I am sure in your area it must have been close to 50°C.

My 5kVa Mecer reached 70° today, I was running around for extra fans.

[Peter Topp]

I agree with Chris Hobson as I have a blown up battery on a large cat generator .

The room is well ventalated but the electrolite levels were not checked.

It does cause rather a mess.

[Jaco De Jongh]

19 hours ago, Chris Hobson said:

electrolyte levels were very low.

 

10 hours ago, Peter Topp said:

electrolite levels were not checked.

Thanks Chris and Peter, strange thing though, the level on the inside cells is just over 1 cm above the plates. the 2 on the ends is basically empty after the explosion , but i have to add the casing got cracked by the explosion causing the electrolyte to run out.  

11 hours ago, GVC said:

it reminds me of how much extra care we have to take with our systems.

I cant agree more. I have learned my lesson with sealed batteries after this incident. I will never use a sealed recreational battery ever again. Maybe someone knows of a way to check the electrolyte on a Royal or similar batteries but i dont. Maybe the level in the 2 broken cells were low, maybe not, but I will definitely replace it with something I can open to check like the rest of my batteries. 

My domestic worker is in that room a few times a day. I dont even want to think what could have happened if she was in there at the time. Luckily we are currently in the process of building her a new  Laundry room and when that is completed she doesn't need to ever be close to this area again ... 

14 hours ago, Johandup said:

It is amazing to look at the damage surrounding the battery in the area in the photo

I agree, the Electrolyte was all over the room after the explosion, what was more amazing to me was the sound the explosion made. Pretty loud for so little gas. 

14 hours ago, Johandup said:

Btw, you need special flameproof equipment when dealing with electric equipment that comes into contact with flammable gases.

Nice point, one that we apply in our work, but who thinks of this when we design or build our solar system. Our inverters and battery normally end up in the same small unused room that we want to close up for security reasons. I dont think a normal inverter casing classifies as a explosion prove enclosure or that the electronics classifies as intrinsically safe. but we survive and I for one has never heard of a solar system exploding.  Your point reminds me that it is indeed possible and that good ventilation should be part of the installation especially where the setup is in a closed small room.  

[Mako]

Good ventilation will not prevent an internal explosion however it will remove free hydrogen which would contribute to the noise.

[maxomill]

a customer of mine had a similar explosion  and said it sounded like a gunshot , and I believe it was due to having almost zero water in the batteries which were 6 years old

cheers

 

[Gabriël]

my sympathy jaco!

i'm very glad no one was injured and no fire resulted - which makes me wonder about my sealed sonic batteries in the garage....

[Weasel]

IMO overcharge either due to temps or settings, you say it was in standby use and should therefore not really get cycle charges. each day a cycle charge applied causing electrolyte to vent off, cells dry out and cause sediment at the bottom of the plates, eventually it all shorts out at causes a rapid heating. Royal granted isnt the best bat but check that you didn't set it incorrectly, i would set float to 13.6 with a -15 to -20 mv per degree C derating and in such standby condition i would limit absorption time to say 2 or 3 hours knowing that it should technically be full most of the time. bulk and absorb id set lower than recommended, more to the standard 14.4 again knowing that it will remain in standby. lastly id put the 75/15 very close to the battery so the temps can be "measured".  if temps in there where say 40c 13.6 should be de-rated to 13.3-13.4 to prevent venting, hope this all makes sense. 

[Johandup]

On the mine we measured the sg in a combination temp hygrometer to determine whether a battery was charged.

We had sophisticated chargers but the above nethod metod was used to switch chargers to different modes.

[Guest]

My 2 cents. Batts will heat up before they explode. It is not a instant thing, it comes over time. Therein the cooking off of the water.

Part of my checking UPS batts, when it was a boom (I only sold Royals), was to touch them when UPS is running to "feel" for hot spots.

It is on my list of what not to do after I burnt my finger seriously on a Royal battery pole, and the battery tested perfect volts. But under load, whole new ballgame.

If the inverter did not pop that day, that battery would have exploded in my face. Got so angry I bought a Hawkins battery tester afterwards.

Back to the point. Feel your batteries for hot spots. Especially if there is a load on them.

 

FWIW. On some of the "sealed" batteries, they have a sticker over the filler caps. On some of them you can pull the sticker off to open the caps. Dixon has such a "sealed maintenance free" 102ah battery.

But I agree, sealed maintenance free lead acid batteries - no thank you. Only in UPS'es inside a strong metal box.