hodgmo
Still Floating
“Lithium battery installations with safe chemistry have been in use for many years, decades for some. I've had them onboard my own and other boats I've distance ocean raced for 6+ years along with 60+ other boats I've helped switch over.”
I’ve driven for more than 40 yrs and never needed seatbelts. Does that mean I shouldn’t wear them?
The fact is that Li-based batteries pose a higher risk of fire than lead-acid batteries because a) Li-based batteries have higher energy density, and b) the electrolyte in the former is flammable whereas it is not in lead acids. (And toxic combustion byproducts are also far more likely to be generated in an accident with a Li-based battery than with a lead-acid one.) There is a wide range of Li-based battery chemistries available and some are much more stable than others, but all Li-based batteries have higher energy density and include flammable electrolytes, which mean that the fire risk is higher than presented by a battery with lower energy density and a non-flammable electrolyte (like lead acid). However, just as some choose to use gasoline or propane even though the presence of those fuels on a boat significantly increases the risk of a fire, the intrinsically higher risk of fire associated with Li-based batteries may be acceptable to some, and the subject risks may be lower than those presented by other aspects of single-handed sailing. Also, I bet nowadays we all have small Li batteries onboard - in our laptops, phones, etc. The difference between the small ones and a house bank is that we have a good chance of being able to chuck the small ones overboard before they do irreparable damage, whereas it may be impractical to deal with an out-of-control house battery.
“The only real way to "slow down" a dangerous chemistry lithium fire is to cover in sand”
I'd like to see a reference that supports this! Sand may be recommended for small, eg, laptop, batteries but larger ‘traction’ Li-based battery fires call for different means. The NFPA appears to recommend that 1st responders use aqueous agents, for example see,
http://www.nfpa.org/~/media/files/r...ports/electrical/ev-batteriespart-1.pdf?la=en
The SAE has also published several studies focused on fire suppression of large Li-based batteries (used in ground vehicles) and I don’t recall any recommending anything other than aqueous agents (or ABC dry chemical or CO2). I’m skeptical of sand as a preferred suppression agent because the open spaces in sand will reduce quenching and allow convection (compared to water for example)… However sand soaked with beer may work well.
http://www.theweatherprediction.com/humor/life/
I’ve driven for more than 40 yrs and never needed seatbelts. Does that mean I shouldn’t wear them?
The fact is that Li-based batteries pose a higher risk of fire than lead-acid batteries because a) Li-based batteries have higher energy density, and b) the electrolyte in the former is flammable whereas it is not in lead acids. (And toxic combustion byproducts are also far more likely to be generated in an accident with a Li-based battery than with a lead-acid one.) There is a wide range of Li-based battery chemistries available and some are much more stable than others, but all Li-based batteries have higher energy density and include flammable electrolytes, which mean that the fire risk is higher than presented by a battery with lower energy density and a non-flammable electrolyte (like lead acid). However, just as some choose to use gasoline or propane even though the presence of those fuels on a boat significantly increases the risk of a fire, the intrinsically higher risk of fire associated with Li-based batteries may be acceptable to some, and the subject risks may be lower than those presented by other aspects of single-handed sailing. Also, I bet nowadays we all have small Li batteries onboard - in our laptops, phones, etc. The difference between the small ones and a house bank is that we have a good chance of being able to chuck the small ones overboard before they do irreparable damage, whereas it may be impractical to deal with an out-of-control house battery.
“The only real way to "slow down" a dangerous chemistry lithium fire is to cover in sand”
I'd like to see a reference that supports this! Sand may be recommended for small, eg, laptop, batteries but larger ‘traction’ Li-based battery fires call for different means. The NFPA appears to recommend that 1st responders use aqueous agents, for example see,
http://www.nfpa.org/~/media/files/r...ports/electrical/ev-batteriespart-1.pdf?la=en
The SAE has also published several studies focused on fire suppression of large Li-based batteries (used in ground vehicles) and I don’t recall any recommending anything other than aqueous agents (or ABC dry chemical or CO2). I’m skeptical of sand as a preferred suppression agent because the open spaces in sand will reduce quenching and allow convection (compared to water for example)… However sand soaked with beer may work well.
http://www.theweatherprediction.com/humor/life/
