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View Full Version : Another hot battery topic,...LAVR



oldLenny
01-13-2004, 06:31 PM
Lead Acid, Valve Regulated batteries in MY opinion have no place in a boat. After spending a week in training on their inherit principles, higher required charge voltage, 77 degree optimum temperature and their "venting" characteristics, they are not suitable in my opinion. I have seen MANY pictures of them, the "roadside" cabinets and 10' x 10' buildings that house them, and the fact that when they go into "thermal runaway", or positive plate expansion, the results look very similar to what USAs' MOAB is cabable of. It is amazing, and they only have a recommended 5 year life span and even that is iffy. Nothing beats a good ol LA (lead/acid) battery in my mind. The LAVR batteries are typically a deep cycle and UPS design. I just know that I would never have one in a boat.

It is such a serious concern now, the brands from all the MAJOR commercial manufacturers, that we have purchased 34-$5000.00 testers to look at them every 3 months on a required routine maintenance check as well as Infra-red thermometers to look for advance signs of this.

The scary thing is we use them in customer premises (banks, etc) for their in house PBX's and routers and such and no one has ever paid attention to these maintenance free beasts. They are pressurized to 3 psi from the factory and blow "off" at 6 psi into the engine compatment in this case. They are VERY finicky to the charge voltage (level of) in relation to their cell temperature/ambient temperature.

The newer Glass-Mat lead acid cells don't exhibit any of these characteristics nor conventional Lead/Acid wet cells. Maintenance free batteries that ARE NOT "LAVR" also don't have these nasty attributes.

Ask someone you know at a local TELCO (central office) about these little bombs and their opinion.

We use them, due to size, little if any off-gasing, and they can be layed down, mounted horizontally, stacked etc. But, if they decide to go, (and 5 years is their max if looked after) they are catastrophic.

Just a tid bit from my last 7 days.

Other tibits,...NEVER jump start or charge a frozen battery. It WILL blow up in a few short minutes as the top of a batteries electrolyte will freeze long before the bottom of then battery and the onset of charging and hydrogen off-gassing will be trapped under the ice on top of the inner cell. A fully charged battery is good for -40 degrees celcius. A dead one will freeze at just below freezing. It should be removed and allowed to warm on its own.

When jump starting a car, turn the running (good) vehicle off, connect the cables to the battery of the GOOD car first, then connect the positive to the bad vehicles battery positive post, and THEN connect the negative to the chassis, bumper, whatever is a good ground point. There will always be an arc to the lower voltage bad battery, and if there is anywheres from 4.1-74.1 percent hydrogen gas to air content it is prime for an explosion. Especially, a maintenance free battery as you can not see where the level is of the Sulpuric acid in relation to the top of the - and + plates and an air void in there will house hydrogen and "could" go off when the spark shows up on the cable connection or just plain ol ignition . Once the cables are all connected you can start the good car first, thus raising the voltage to about 14.5-14.7 and then start the bad car. Remove the cable from the bumper or ground point on the bad car and then there is no chance of creating sparks around the batteries.

Last thing...do you know what the difference is between a 2 year battery, a 3 year battery, and a 5 year battery???

The Companies have figured out how long the electrolyte (sulpuric acid) will last above the plates under normal use and timeline. They simply "overfill" (not really, but fill higher) the amount of electrolyte in the battery prior to sale to the wholesaler...brutal...

Also, I have had 2 12v batteries in vehicles blow in my lifetime while starting them (luckily from inside the cab) It will raise raise your hood and destroy everything in sight.

Fish boy
01-13-2004, 06:40 PM
Thanks Lenny, good info. Never really thought about until now.

MOP
01-13-2004, 07:57 PM
Lenny is this the same type that were blowing up cell phones, I caught something on TV news about it but did not pay much attention.

Phil

oldLenny
01-13-2004, 08:53 PM
MOP, no, I believe they were the Nickel Metal Hydride. All batteries run on similar priciples mind you and 2 volts/cell is 2 volts. Storage/plate materials differ to some degree as well as the electrolyte component and inherit qualities.

mattyboy
01-13-2004, 10:03 PM
Pardon me but what kind a cells are those !!!
they shake like nickel hydryde but look to perky to be lead acid?????
must be silicone

( eek! ) ( eek! )


Matty

I betcha her boy friend don't hear the phone ring in the morning either!!!!

MOP
01-14-2004, 06:44 AM
Now worried I have a Radio Shack Nickel Metal Hydride, which honestly has given me exceptional service and much longer usage between charges. Hate to dump it, are there comparable alternatives or ways to avoid the problem.

By the way Lenny you not only walk funny but talk funny :D :D :D
I know you are thinking the same :D :D :D