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12v battery indicator with flashing leds showing state of charge when recharcing Answered

Hi guys.

I have a 12v lead-acid battery and i want to make a circuit, which can show me state of charge of the battery with 5 (blue or white) leds. When the battery is in use, it should light up all 5 leds at 100%, 4 at 80%, 3 at 60%, 2 at 40% and 1 at 20%.

Now when i want to charge the battery i would like them to light up in order, as it gets recharged. Lets say it has 0% capacity left and i plug in the charger, the first led should start flashing/blinking. When the battery has charged to over 20%, the first led should turn solid and the second led should start flashing, which indicates that the battery has recharged somewhere in between 20-40% battery life. This goes on until it has reached 100% and all leds should light up solid. When the battery is in use (no charger plugged in) the leds should flash like this, just turn off as explained in first.

Furthermore i would like to add a switch, which can turn on/off the indicators (but not the battery and charger itself)

To see what i mean, i saw that soundboks, has added this feature in their batteryboxes: https://www.youtube.com/watch?v=rlY8B2dHYD4 (watch 0:50)

Is this something someone can help me with?


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Reply 1 year ago

Hi Orngrimm, thanks for you answer.

You see, the problem is that these indicators only does the job when the battery is outputting power to a circuit.
When i want to recharge the battery, i would like the first led to flash, which indicates that, lets say 0-20% is being recharged atm. When battery gets over 20%, the first led should turn solid and next led should start flashing, which indicates that 20-40% battery stage is being recharged.