volroom
Race Dog
I got the Ultrabatt, the UB600 end of last year from Bike Gear. Thought the benefits of it lasting up to 10 years, and it weighing in at a measly 1.1kg could justify that cost. These batteries are still quite expensive, lithium batteries. Long story short, it seems that you have to be careful when looking to buy a lithium (iron phosphate) battery for your pig... the idea with these batteries seems to that since it has a low resistance (compared to lead acid) it can provide a much greater current. With lead acid batteries, to get the current you need (up to 200A), you need a high capacity battery. For our pigs, they recommend around 20Ah. So, a 10 Ah lead acid won't do it...
But, a true 10Ah lithium battery would swing that engine better than a 20Ah lead acid - because of low resistance, greater current even though less capacity.
So, I'm imagining the brain wave was: how small a lithium battery would be able to start the engines of various motorcycles...turns out that you can have tiny lithium batteries doing the job.. a 1.1kg (6.9Ah) lithium battery starts you pig better than a 5kg (20Ah) lead acid battery. We just need to get the engine to start, after that the alternator will keep the battery charged...so let's have tiny lithium batteries for lots of money (lithium is quite scarce). They are looking into sodium batteries BTW.
The problem is that there are things like parasitic drain (when bike is switched off), which will drain a tiny battery much faster than a big one. And...lithium batteries DON'T like cold, at all. Even Sunny SA can get cold in the winter mornings.
So, my experience. Down to CT in April, in Colesberg, in the morning, the starter pulled that battery dead - my clock reset. I thought, this is impossible.....so, it must be the starter motor. Maybe the magnets are loose. Had a look, nope..they were fine.
So, I'm worried. It happen again at another stage. Fortunately, there's a warranty, so I'm getting back the cash. Want to invest in a proper AGM. https://www.rgsound.it/ep12-16ep-0769-2007-12v-16ah-elevatissimo-spunto_genesis-batteries-id-16619.html
They're not cheap, and they are heavier by about 1.5kg (lead is much more pure, and heavy..). It's 16Ah, which you'd think is not 20Ah, but because it also has lower resistance (because of much purer lead), it can deliver a greater current. These batteries seems tough, and if well tended..can last up to 10 years...
Problem: our alternators...seems that they are not that how with the voltage. I've got a voltmeter installed. I'm getting an average of 13.9V. If it's really cold, I'd get up to 14.14V, but that's because the wires are cold, lower resistance, less voltage needed to push current through them.
These batteries need to so 14.5V plus to keep them happy. providing 13.8-13.9V is not good for that battery. Put it like this; it won't last as long. LeCap, your input here please..
There's a guy on ADVrider that modified his alternator, but replacing a diode (the rectifier), and is getting higher voltage now. You see, the problem is not the current that our alternators is providing. At 720W, and 13.9V, you can get 51.9A - which is much more than the needed charging current, but voltage plays a role. There is some resistance in these batteries, and to truly charge them up to max, you need sufficient voltage.
Some guy on ADVrider has said that our alternators only providing 13.9V is a problem..a problem that BMW should have rectified (excuse the pun).
So yah...I want this battery, but I want my alternator to charge it properly... any thoughts?
But, a true 10Ah lithium battery would swing that engine better than a 20Ah lead acid - because of low resistance, greater current even though less capacity.
So, I'm imagining the brain wave was: how small a lithium battery would be able to start the engines of various motorcycles...turns out that you can have tiny lithium batteries doing the job.. a 1.1kg (6.9Ah) lithium battery starts you pig better than a 5kg (20Ah) lead acid battery. We just need to get the engine to start, after that the alternator will keep the battery charged...so let's have tiny lithium batteries for lots of money (lithium is quite scarce). They are looking into sodium batteries BTW.
The problem is that there are things like parasitic drain (when bike is switched off), which will drain a tiny battery much faster than a big one. And...lithium batteries DON'T like cold, at all. Even Sunny SA can get cold in the winter mornings.
So, my experience. Down to CT in April, in Colesberg, in the morning, the starter pulled that battery dead - my clock reset. I thought, this is impossible.....so, it must be the starter motor. Maybe the magnets are loose. Had a look, nope..they were fine.
So, I'm worried. It happen again at another stage. Fortunately, there's a warranty, so I'm getting back the cash. Want to invest in a proper AGM. https://www.rgsound.it/ep12-16ep-0769-2007-12v-16ah-elevatissimo-spunto_genesis-batteries-id-16619.html
They're not cheap, and they are heavier by about 1.5kg (lead is much more pure, and heavy..). It's 16Ah, which you'd think is not 20Ah, but because it also has lower resistance (because of much purer lead), it can deliver a greater current. These batteries seems tough, and if well tended..can last up to 10 years...
Problem: our alternators...seems that they are not that how with the voltage. I've got a voltmeter installed. I'm getting an average of 13.9V. If it's really cold, I'd get up to 14.14V, but that's because the wires are cold, lower resistance, less voltage needed to push current through them.
These batteries need to so 14.5V plus to keep them happy. providing 13.8-13.9V is not good for that battery. Put it like this; it won't last as long. LeCap, your input here please..
There's a guy on ADVrider that modified his alternator, but replacing a diode (the rectifier), and is getting higher voltage now. You see, the problem is not the current that our alternators is providing. At 720W, and 13.9V, you can get 51.9A - which is much more than the needed charging current, but voltage plays a role. There is some resistance in these batteries, and to truly charge them up to max, you need sufficient voltage.
Some guy on ADVrider has said that our alternators only providing 13.9V is a problem..a problem that BMW should have rectified (excuse the pun).
So yah...I want this battery, but I want my alternator to charge it properly... any thoughts?
