In recent years, we don’t see these open-type batteries much anymore.
There have been cases of poor maintenance, fluid damage, and explosions, so I hope this will be helpful as a reference.
• Poor maintenance
Open-type batteries require checking the fluid level as an essential task.
The manufacturer’s specifications call for charging every three months and checking the fluid level monthly.
Setting aside the charging, checking the fluid level requires removing the battery, which is quite a hassle.
※ Be careful not to overfill above the fluid level line.
※ Always use “battery-grade distilled water” for topping up. Do not add dilute sulfuric acid. Also, be careful not to use well water or tap water, as impurities can cause excessive self-discharge and shorten battery life.
A common pattern of poor maintenance is the battery dying while out and about. This happens when the battery fluid level drops completely and the battery stops working.
I haven’t seen or heard of it myself, but apparently if the battery fluid gets too low, sparking can occur inside and the battery can explode. Scary stuff!
• Fluid damage
Battery fluid uses dilute sulfuric acid. Topping up uses “battery-grade distilled water.”
During battery use (charging), oxygen and hydrogen gases are generated, creating a risk of ignition and explosion, so open flames are strictly prohibited.
A case I happened to witness firsthand.
A customer rode into a shop (not ours, mind you) and right away asked for a chain replacement.
The shop staff ground down the chain rivet head with a grinder, sparks flying everywhere—”whirrrrr”—and then the next second!
“BOOM!” came the explosion sound and battery fluid went splashing down everywhere.
The swingarm and linkage area, even after washing, was all pitted and corroded.
Seeing that, I honestly thought “Wow, that’s scary” (；∀；)
Other issues include corrosion of the battery case and surrounding parts. A bent battery breather hose can cause battery swelling—open batteries are surprisingly delicate when you think about it.
You can’t even lay them on their side when transporting them for disposal.
When you think about maintenance, fluid damage, explosions, and everything else, only drawbacks come to mind—I can’t see any benefits at all.
These days there are drop-in replacements available: Pro Select Battery AGM GEL.
When replacing the battery, please use Pro Select Battery AGM GEL. (‘ω’)ノ
