Charging problems with lithium batteries | GTAMotorcycle.com

Charging problems with lithium batteries

wtf was that? It could have been good but they screwed up so many things it was basically a bad infomercial.

300 amp hour battery? The standard alternator burned up at low speed so they ran the "good" alternator at higher speed and said it was better? They couldn't run the alternators over 3600 rpm because that was their max motor speed? They had a belt drive and VFD, that is a at least two paths to higher rpm. When the cheap alternator burned up it was at 1500 rpm. Aren't most engines running the alternator at two to four times engine speed? The whole thing was just so flawed you can't draw any conclusions from it for a normal use case.
 
wtf was that? It could have been good but they screwed up so many things it was basically a bad infomercial.

300 amp hour battery? The standard alternator burned up at low speed so they ran the "good" alternator at higher speed and said it was better? They couldn't run the alternators over 3600 rpm because that was their max motor speed? They had a belt drive and VFD, that is a at least two paths to higher rpm. When the cheap alternator burned up it was at 1500 rpm. Aren't most engines running the alternator at two to four times engine speed? The whole thing was just so flawed you can't draw any conclusions from it for a normal use case.

I think it was to push a product but it did point out that one has to think about the whole system and understand the dynamics.

That looked like a massive battery and the relevance would depend on a number of factors starting with bike, car or boat. The fan cooling factor caught me off guard.

I related this more to a boat conversion where someone just dropped a big L-ion battery into the bilge and expected the stock alternator to charge it up after a day of using the trolling motor.

I did regulator to alternator conversions on a motorcycle and an inboard boat motor and matching RPMs of motors and alternators can be a bit of a compromise.
 
I think it was to push a product but it did point out that one has to think about the whole system and understand the dynamics.

That looked like a massive battery and the relevance would depend on a number of factors starting with bike, car or boat. The fan cooling factor caught me off guard.

I related this more to a boat conversion where someone just dropped a big L-ion battery into the bilge and expected the stock alternator to charge it up after a day of using the trolling motor.

I did regulator to alternator conversions on a motorcycle and an inboard boat motor and matching RPMs of motors and alternators can be a bit of a compromise.

Agree. There does need to be thought put in, but they should also have put some of that thought into their testing. Very few alternators would ever spin slower than 2400 rpm but that probably wouldn't burn up for the video. Making an argument based on flawed testing does nothing constructive. I like the concept of something monitoring temperature and adjusting current although they were monitoring case temperature which would both lag winding temperature by a lot and may not even be correlated depending on the sensor location and airflow. Having something actively adjusting current based on a potentially flawed and at the very least very laggy indicator makes you feel better but is probably not actually that helpful.

I think the best bet for any lithium conversion is to put a brain box between the vehicle and battery. That box can provide voltage/current protection for the battery as there are legitimate charging issues with lithium and some vehicle charging systems (IIRC over voltage from charging lets the smoke out of the lithium battery).
 
Lithium batteries aren't a common mod in the car world ... maybe only for "summer cars".

In the motorcycle world, I've never heard of an alternator blowing up like this. The majority of them are bolted to the crankcase and in very good thermal contact with the crankcase. The bikes that have a reputation for blowing up stators, do so regardless of battery.
 

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