Taking care of Marine Grade, RV & Automotive Batteries
Care for batteries
Batteries are not all the same. Each battery technology (lead acid, lithium, etc) requires a different level of care and must be handled differently.
Lead Acid batteries:
The most common battery that people will encounter at the time of writing this is the lead-acid battery. The enemy of these batteries is sitting, especially in a discharged state. A lead-acid battery that is stored fully charged and topped up once a month can last years.
There are 6 cells in a typical automotive / RV battery, each providing 2.1 volts. Each cell has a positive and negative plate. When discharged the sulphuric acid (aka battery acid) loses its sulphur particles which will coat the plates and create electricity, conversely while recharging the plates are energised and push the sulphur back into solution and you have a charged battery.
Batteries self-discharge at a rate of 1% to 3% per month. When a battery is left in a discharged state, the electrolyte (sulphur) that is already on the plates will crystallize.
This process is called “sulphation”. If enough sulphur builds up in the battery and touches both lead plates the cell will short and die and you will lose 1/6th the power of the battery. Discharged batteries also risk freezing, the electrolyte in a discharged battery is more similar to water and will freeze around -7c
Always leave lead-acid batteries in their most charged state as often as possible. If the battery is not in use it should be hooked up to a trickle charger that will constantly monitor the battery and will turn on to recharge the battery as it slowly discharges itself. The charger needs to be the “smart” variety because overcharging the battery will cause it to boil, emit gas hydrogen and lose electrolyte. Use a charger like “Noco”.