Always wear safety glasses whenever doing anything with any batteries (acid/arcing protection)
Have a fire extinguisher at ready.
A bucket of water is useful for acid burns or fire etc.
When installing them be careful with your hold down brackets.
Make them fit closely, although well clear of the terminals and connections allowing for future cabling. Insulate them if need be.
Make them VERY strong. (It needs to be strong due to the fact most of these batteries weigh up to twice a normal battery of the same size)
Make them large to distribute the clamping force over a large area of the battery
DO NOT OVER TIGHTEN the hold down clamps.
It is ESSENTIAL not to tighten them down too hard although they must be secure(especially with a small surface area bracket)
What happens if you do, you run the chance of popping the plastic weld on the case, you most likely won't see it, but when this happens you then turn this battery into an open cell that can gas and lose water. The battery is designed to recombine its gas under pressure in a sealed container, yes it has pressure release valves if it gets too high, but if the case is split on the weld then it can vent to the atmosphere and your battery will die a premature death.
When installing them, be aware that they are generally very heavy. Some weigh 35KG/77lbs or even more. this makes them extremely hard to place and/or remove in a tight battery spot. It also may put you in a position of strain/damage to your back etc. trying to hold these batteries out in front of you or by over extending.
Be careful when installing battery posts or cable terminals to threaded terminals, do not over tighten, you can destroy the seal around the battery post and end up with the same result as above. (Get the manufacturers tightening torque and use a tension wrench)
Never use a battery carrier strap that goes across each terminal to lift the battery.
When tightening battery terminals to the battery posts, support the terminal so less stress is placed upon the post when tightening to stop it cracking the seal.
Be extremely careful when installing the battery. Cover each terminal with some insulation (a couple of layers of 100mph tape over each terminal or similar) so that you don't accidentally short out the terminals with a spanner or the hold down bracket. These batteries are capable of up to 5000 amps short circuit current - thats a damn big welder - and can create fire/explosion/arcing.
When installing them only remove the terminal insulation from one terminal at a time. Fit that terminal and associated wiring complete with insulating terminal covers before then doing the next terminal. As most installations involve a second battery, insulating your spanner with some tape so you don't short to the vehicle ground is a good precaution. This can happen even if the ground is not connected on the battery you are working on due to the fact your connection cable from the other battery may be "live".
Ensure all connections are clean and free of grease/dirt/petroleum jelly etc. before making them. (A green 3m Scotch scouring pad with some solvent/wax and grease remover does a good job, wipe with a clean cotton rag after this)
If you must use something on your terminals (DON'T), put it on after all connections are made, not between the connections. I don't recommend using anything on them as these batteries gas very little, you should be able to get away without anything on there and there should be minimal corrosion with no acid fumes around. (A photo of my connections below)
Stainless steel hold down brackets are a good choice for any battery.
Insulate these batteries from heat under your bonnet to give them the best chance for long life. A battery which is constantly HOT will die a premature death due to excess gassing. Ensure your insulation is rated for high temperatures and if possible use flame retardant insulation as exhaust heat may ignite some materials.
When using dual AGM batteries with a dual battery isolator, ensure they disconnect your starting battery at 12.5 volts or above to protect your battery from excessive drain from you fridge or accessories. AGM batteries generally run at higher voltages and their discharged voltages are higher as well. I have seen some battery isolators disconnecting at 11.4 volts. If you look at the table below (Optima Red and Yellow specifications, Blue is either a Red (dark cased blue) or a Yellow (light cased blue with a D in the model number)) you will see where this leaves your starting battery.
My thoughts only, please seek professional advice.
Have a fire extinguisher at ready.
A bucket of water is useful for acid burns or fire etc.
When installing them be careful with your hold down brackets.
Make them fit closely, although well clear of the terminals and connections allowing for future cabling. Insulate them if need be.
Make them VERY strong. (It needs to be strong due to the fact most of these batteries weigh up to twice a normal battery of the same size)
Make them large to distribute the clamping force over a large area of the battery
DO NOT OVER TIGHTEN the hold down clamps.
It is ESSENTIAL not to tighten them down too hard although they must be secure(especially with a small surface area bracket)
What happens if you do, you run the chance of popping the plastic weld on the case, you most likely won't see it, but when this happens you then turn this battery into an open cell that can gas and lose water. The battery is designed to recombine its gas under pressure in a sealed container, yes it has pressure release valves if it gets too high, but if the case is split on the weld then it can vent to the atmosphere and your battery will die a premature death.
When installing them, be aware that they are generally very heavy. Some weigh 35KG/77lbs or even more. this makes them extremely hard to place and/or remove in a tight battery spot. It also may put you in a position of strain/damage to your back etc. trying to hold these batteries out in front of you or by over extending.
Be careful when installing battery posts or cable terminals to threaded terminals, do not over tighten, you can destroy the seal around the battery post and end up with the same result as above. (Get the manufacturers tightening torque and use a tension wrench)
Never use a battery carrier strap that goes across each terminal to lift the battery.
When tightening battery terminals to the battery posts, support the terminal so less stress is placed upon the post when tightening to stop it cracking the seal.
Be extremely careful when installing the battery. Cover each terminal with some insulation (a couple of layers of 100mph tape over each terminal or similar) so that you don't accidentally short out the terminals with a spanner or the hold down bracket. These batteries are capable of up to 5000 amps short circuit current - thats a damn big welder - and can create fire/explosion/arcing.
When installing them only remove the terminal insulation from one terminal at a time. Fit that terminal and associated wiring complete with insulating terminal covers before then doing the next terminal. As most installations involve a second battery, insulating your spanner with some tape so you don't short to the vehicle ground is a good precaution. This can happen even if the ground is not connected on the battery you are working on due to the fact your connection cable from the other battery may be "live".
Ensure all connections are clean and free of grease/dirt/petroleum jelly etc. before making them. (A green 3m Scotch scouring pad with some solvent/wax and grease remover does a good job, wipe with a clean cotton rag after this)
If you must use something on your terminals (DON'T), put it on after all connections are made, not between the connections. I don't recommend using anything on them as these batteries gas very little, you should be able to get away without anything on there and there should be minimal corrosion with no acid fumes around. (A photo of my connections below)
Stainless steel hold down brackets are a good choice for any battery.
Insulate these batteries from heat under your bonnet to give them the best chance for long life. A battery which is constantly HOT will die a premature death due to excess gassing. Ensure your insulation is rated for high temperatures and if possible use flame retardant insulation as exhaust heat may ignite some materials.
When using dual AGM batteries with a dual battery isolator, ensure they disconnect your starting battery at 12.5 volts or above to protect your battery from excessive drain from you fridge or accessories. AGM batteries generally run at higher voltages and their discharged voltages are higher as well. I have seen some battery isolators disconnecting at 11.4 volts. If you look at the table below (Optima Red and Yellow specifications, Blue is either a Red (dark cased blue) or a Yellow (light cased blue with a D in the model number)) you will see where this leaves your starting battery.
My thoughts only, please seek professional advice.
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