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Forum Index : Electronics : Inverter building using Wiseguys Power board and the Nano drive board
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wiseguy Guru  Joined: 21/06/2018 Location: AustraliaPosts: 1294 |
I am far from an expert on large lithium storage but have visions of what a large battery ~120kG would behave like if it ever went feral. I would not like to be within 10-20 metres of the action and the concept of pushing/pulling/steering/guiding a 2 metre unpredictable flame thrower whilst spewing dense toxic fumes is the stuff of nightmares. Maybe put the batteries on a ramp headed towards a battery backed remote control door and with a battery backed solenoid pin retract to then send it off somewhere else sounds like a more appropriate plan to me. I am not sure a neighbour would be excited to receive it either  If that is over the top or exaggerated, please tell me what to really expect, I am happy to be educated further. Edited 2026-06-15 10:48 by wiseguy If at first you dont succeed, I suggest you avoid sky diving.... Cheers Mike |
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phil99 Guru Joined: 11/02/2018 Location: AustraliaPosts: 3285 |
That can be an issue with lithium ion cells as they use a hydrocarbon electrolyte with similar flammability as petrol. An internal short will release enough energy to boil the electrolyte and burst the cell. Boiling petrol + air + sparks = not good. LiFePO4 cells are much safer. As with almost all battery types overcharging may cause them to vent hydrogen, which can build up in a poorly vented space. As it is lighter than air it clears quickly if there is ventilation at ceiling height. The other risk is an internal short causing an extremely rapid release of the stored energy. No more common than with large lead-acid cells. |
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Revlac Guru Joined: 31/12/2016 Location: AustraliaPosts: 1269 |
There are many more things in everyday life that are far more dangerous and more likely to happen and often do. There is probably a better place to post this stuff.  Edited 2026-06-15 12:02 by Revlac Cheers Aaron Off The Grid |
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KeepIS Guru Joined: 13/10/2014 Location: AustraliaPosts: 2172 |
Big difference between older lithium chemical stews, still being sold, and LiFePO4. The toxic flame thrower you see in older EV, Home solar and E-bikes etc, are older lithium battery chemistry. Unfortunately Main Stream Media and social media affiliates, never ones to let a chance to scare and alarm viewers who still watch them, will not differentiate or identify the type of lithium battery chemistry involved, fortunately the numbers of viewers are getting less and less as people finally wake up to there cowardly & ignorant games. If you manage to get a LiFePO4 to vent, it will only vent, to start a fire, it still needs a specific set of circumstances to ignite any "concentrated buildup" of vented vapour. The cells do not spontaneously runaway or burst into flames. As far as neighbours being concerned, they should be concerned about all the older chemistry Home Solar batteries installed next door or their own install, over the past five years, or even older. NANO:Inverter V 8.2ks - Linux AvrDude GUI script V4.1 |
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| wiseguy Guru Joined: 21/06/2018 Location: AustraliaPosts: 1294 |
Thanks for the replies and education guys - I have seen clips of vehicle batteries acting as 2 metre flame throwers and yes, I fell for the "bad lithium" hype. I also accept that LiFePO4 are a better chemistry but after seeing that recent shed blown apart with them I still have some reservations & yes ok most probably unfounded. Noted & sorry for the pollution..... Edited 2026-06-15 14:14 by wiseguy If at first you dont succeed, I suggest you avoid sky diving.... Cheers Mike |
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Bryan1 Guru Joined: 22/02/2006 Location: AustraliaPosts: 2084 |
While we are on the topic I just had to google it and here is the AI reply on these batteries.  AI Overview Yes, LiFePO4 (Lithium Iron Phosphate) batteries can technically catch fire, but it is extremely rare. They are significantly safer than traditional lithium-ion batteries.LiFePO4 batteries have a highly stable molecular structure. Unlike cobalt-based lithium chemistries, they do not easily release oxygen when damaged, which means a LiFePO4 fire is generally not self-propagating and is much harder to ignite. However, they can still catch fire or release dangerous gases under extreme circumstances :1. External Heat and FireWhile the cells themselves are stable, the internal electrolyte is flammable. If the battery is placed into an external fire (like a house or engine fire), the casing will eventually melt or breach, allowing the electrolyte to spill and ignite. 2. Severe Physical DamagePuncturing or crushing a cell can cause a massive internal short circuit. This direct short can generate enough heat to cause the cell to glow red-hot, vent, or ignite the internal chemicals. 3. Faulty or Missing BMS (Battery Management System)A Battery Management System (BMS) is the electronic brain that protects the battery from overcharging, over-discharging, and dangerous temperatures. If the BMS fails or is absent, the battery can be pushed into a state where it vents white gas. This gas contains a high volume of hydrogen and can explode if exposed to an ignition source in a closed space. 4. Poor Installation and WiringMany "battery fires" are actually electrical fires. Using incorrectly sized wires, poorly crimped connectors, or incompatible chargers can generate intense heat at the connection points, leading to a fire outside of the battery itself Now with that 730AH battery I put in my shed back in '13 a while ago I was cutting some 1mm gal plate and heard a bang. After a while I noticed one of the cells at the end of the case had blown the top off the cell. Now that battery still works fine and a big NO it didn't set of a chain reaction. No BMS needed and only a fuse is required to stop any short circuit condition. But as lead acid batteries are old school they still outlive any lithium battery by a long shot. Regards Bryan |
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| KeepIS Guru Joined: 13/10/2014 Location: AustraliaPosts: 2172 |
Great if you live on a farm or very large building block: How much does the 730AH weigh? How much floor space does it occupy? How much solar power do you need to feed back into the battery to replace the power drawn from the battery? IE: What is the charge/discharge cycle efficiency? All of this has an impact on the space requirements for number of solar panels and battery location and storage on a small suburban block. NANO:Inverter V 8.2ks - Linux AvrDude GUI script V4.1 |
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