Yea what is the temp?
ABRV4 said:
Odyssey warns that the plastic case of their batteries can balloon out if the battery is mounted in a "high temperature" location and is not placed in their steel mounting box. Has anyone had a problem with heat effecting their Odyssey battery when it is forward of the firewall and not in the steel box? Thanks.
Alan
RV-4
I and others have worried about this as well. Seems to work but life could be some what reduced with high temps.
I suspect after shut-down on a hot day, cooking on a hot ramp, may be the worst case scenario. In flight with air flow its probably that bad. Any one take temp readings? I suspect with it up against the metal firewall its getting some cooling. The scientific answer is measure it.
The Odyssey spec book says 176F max operating temp. There is some safety factor on that temp I suspect. I saw one Odyssey that was WAY OVER CHARGED for way too long. It indeed did puff out and was bulging all over.
BAT charging also makes heat, so after shut down you take the charging heat away even though it may cook a little as the cowl heat soaks. You always have the option to add a blast tube and heat shields. Side note some advanced voltage regulators have a BAT temp probe, which fine tunes charge voltage to keep bat temp in-line.
There is also radiant heat. You don't want the battery to be looking at or have line-of-sight to any real hot component, like exhaust, so a heat shield on nearby super-hot parts can be beneficial. Wraping the exhaust is not a good idea since it can cause cracks and hide them as well. Some use ceramic coating, but its hard to get good coverage on the inside. Ceramic coating just on the out side can have similar affect on cooking the pipes as well, but ceramics and wrapping exhaust is a whole other debate.
After shutdown during the cook-off, convective heat takes over. Opening the oil door helps vent-off or chimney the heat out. You could take it further and install a cooling vent on the upper cowl to let more hot air escape. I saw that in a tony bingelis book. If there was an easy way to keep the BAT cool or cooler, I'd do it, but like every thing on a plane its a trade-off. The Fwd bat position is good for CG (on a RV-7) and also simplifies the BAT wiring a little, at least for the starter. The temp is not ideal but acceptable.
I'm not going to worry about it but will measure the temp. RV's have a tight cowl verses old GA planes with much larger cowls. Temps had to be lower in those factory planes, so some concern or attention to temps should be paid to your RV's alternator, battery and accessory installations. The alternator should be kept cool for long life. The electronics are good for 125C to 150C which is over 250F. However that's temp from making power and its environment. When its getting to 150F to 180F around the the alternator (like the battery) its getting too hot in my opinion, so blast air and heat shields may add life to the alternator and battery.
