Gel Battery

Hi,

After rebuild of the XJ900F I put in a new regulator/rectifier, cleaned all electrical connections and put in a new Gel type battery.

Now after about 3 relatively short rides (around 20 kilometres each) it appears that the battery has died or shorted out. I put the multimeter on it and when I turn on the ignition the meter shows a drop from around 12 volts to...3 volts!

I did read in the XJ4ever pages the only reference to a gel battery being..."this is not a battery type you want to use for your XJ's".

From my reading on the web it appears gel batteries are very susceptible to the charging system and our old bikes might be a little Neanderthal and heavy handed in that department.

Can anyone confirm please. About to buy a new battery and current experience suggests to go back to a traditional lead acid battery. In 10 years I hardly had any problems with them.

Thanks!

 

I have sealed(AGM) batteries in all my old Yamahas , never had any problems with them. I like them, no acid spills and more CCA.

 

Traditional acid or AGM batteries work fine. I run an AGM as well for same reasons as mlew.

 

+1, my next battery will be AGM

 

AGM in my 3 bikes and I like 'em

for a few words on the topic
https://www.batterystuff.com/kb/articles/battery-articles/gel-vs-agm.html

 

AGM and Gel are not the same thing. a agm is like a jelly roll with lead and fiberglass mat rolled up like a jelly roll them soaked in acid and sealed. a gel is more like a old fashioned lead acid battery
with acid jello in place of liquid acid. i've dropped both out of a bucket truck and seen the difference the gel don't seem to like high charge/ discharge but i've used them with no problems.
check the voltage regulator for high output

 

Thanks.
I have a feeling the regulator might have caused my Gel battery to die prematurely. My readings on the web seem to indicate that they are sensitive to the charging rate. Perhaps the charge rate from the regulator might be too high for the Gel...more to do with amperage than voltage?

 

The regulator will only put out what the load draws until it hits the regulators limit. So if a regulator is capable of 8 amps but the battery only draws 6 max, the regulator is not going to "cram an extra 2 amps" into it. The issue with gel is the charging profile is different. Gel batteries require a special charging circuit (usually in applications designed for it although I've seen adapters) or a battery with a built in management circuit.

 

the greater the difference between the battery voltage and the alternator voltage will determine the current.
so
if the bike starts right up and the lights don't get left on the battery voltage will stay close to the alternator voltage, low charge current, battery lasts a long time
but
if it's hard to start and the battery gets low often the alternator will charge the heck out of it and it won't last so long

 

Just as a follow up to this I put in the new AGM battery and everything is back to normal but just as a precaution I did a test with the multimeter while the engine is running/revving and the charge rate shows from 14.5 volts to well over 15 volts (and jumped to 17+ volts briefly at times) at 2500-3000 rpm. I think the regulator is well and truly gone and probably cooked the older battery. I've got a spare brand new regulator (from Len) so will swap over on the weekend and test.

 

Anything over 14.8 is indicative of a faulty regulator. Better swap before you cook another battery!

 

Yep. On the job now.

The relatively inexpensive dud brand new Reg/rectifier bought off eBay...dubious origins perhaps and now dubious performance.

No doubt the rectifier from Len/Chacal will work properly and be a good companion to the new AGM battery.

I tell my kids you get what you pay for...I'm not telling them I didn't follow my own advice!

Thanks for your comments and help.