Learn About Lead Acid Battery Care in Redding, CA
Most problems with battery-based systems using lead-acid batteries have to do with the condition of the batteries and connections. You must keep the connections clean of any corrosion. Corrosion comes from the acid in the battery getting out and contacting the lead post and connections.
Overwatering can cause the acid to leak when the battery is charging, and the water level rises due to the bubbles forming on the lead plates in the battery. If you see corrosion, you must shut the system down and take the connection apart to properly clean it, cleaning the outside of the connection does nothing for keeping the connection good for energy transfer in and out of the battery.
Battery Maintenance Procedure
Recommendations
- Check the water level once per month: It should be kept at 1/4” to 3/8” below the bottom of the filler neck. The filler neck is the plastic insert that is below the filler cap. USE DISTILLED WATER ONLY!
- Check the voltage of each 6-volt battery (or each 2-volt cell if you have 2v batteries) once every three months: THIS READING MUST BE AT RESTING VOLTAGE! Write this info down on a log sheet. It is best if you make a ‘map’ of your battery bank, so it is easier to keep track of which voltage corresponds to which battery (or which cell). You don’t have to disconnect the cables to do this. Just put the voltmeter cables to the battery posts. “Resting voltage” and “resting status” means no power going into or out of the batteries for 30 – 60 minutes. If the highest to the lowest battery is close to or @ 1/10th of a volt, YOU MUST DO AN EQUALIZE CHARGE TO GET THE VOLTAGES EVEN AGAIN. If this is not done, the low batteries will continue to drop until the cells start failing completely.
- Check the hydrometer readings: if you suspect there is a problem based on the voltage reading, you can use a floating cam style hydrometer or a floating ball style. Write down the numbers on your battery map, not the green, yellow or red color.
- Clean the battery cable connections and battery tops: use a solution of water and baking soda. You can mix 1/2 pound of baking soda into 1/2 gallon of water. Be very careful not to get this solution into the battery cells.
- Check for any amount of corrosion on the battery connections: Disconnect the cable and clean the cable and the terminal with a wire brush and the baking soda solution. After everything is clean and put back together, use a paintbrush or rag and wash the top of the batteries with the soda solution to neutralize any acid, then rinse with water, you can even hose the batteries off. You won’t get electrocuted! Be very careful when working with battery connections. Tape the handle of your wrench, so you don’t short it out if you touch two posts together or drop your wrench! Put a light coating of Vaseline on the post & cable ends before assembling. This is an easy way to keep acid off the connections. Once each year, you should disconnect all the battery cables and clean the cable ends and the battery posts. Use the baking soda/water solution and a wire brush for this operation. You should do this even if you don’t see corrosion on the connections to be sure the connections are as clean as they were when it was new.
Battery State of Charge Sheet
Deep-Cycle Flooded
These numbers are for a battery that is in a RESTING STATUS. That means no power going in or out of the battery for 30 – 60 minutes. In other words, no charging and no usage. Turn off the charging and the inverter.
TABLE 2. Deep-Cycle Flooded – State of charge as related to specific gravity and open-circuit voltage
Percentage of Charge | Specific Gravity
(Corrected to 80º F /27º C) |
Open-Circuit Voltage | |||||
6V | 12V | 24V | 36V | 48V | |||
100 | 1.277 | 6.37 | 12.73 | 25.46 | 38.20 | 50.93 | |
90 | 1.258 | 6.31 | 12.62 | 25.24 | 37.85 | 50.47 | |
80 | 1.238 | 6.25 | 12.50 | 25.00 | 37.49 | 49.99 | |
70 | 1.217 | 6.19 | 12.37 | 24.74 | 37.12 | 49.49 | |
60 | 1.195 | 6.12 | 12.24 | 24.48 | 36.72 | 48.96 | |
50 | 1.172 | 6.05 | 12.10 | 24.20 | 36.31 | 48.41 | |
40 | 1.148 | 5.98 | 11.96 | 23.92 | 35.87 | 47.83 | |
30 | 1.124 | 5.91 | 11.81 | 23.63 | 35.44 | 47.26 | |
20 | 1.098 | 5.83 | 11.66 | 23.32 | 34.97 | 46.63 | |
10 | 1.073 | 5.75 | 11.51 | 23.02 | 34.52 | 46.03 |