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Hi, we have 100 AH @48 V lithium batteries installed at site , I wanted to ask about it's charging algorithm, do we need absorption stage in lithium batteries? What is difference between equalization and absorption voltage , do we need cyclic equalization/ absorption voltage in lithium batteries?please clarify I have confusion regarding charging of batteries.
Regards,
Inam
If you have the time, then watch the videos of Andy from Offgrid Garage. There you will find a lot of detailed information.
In short, - you definitely need the absorption phase if you want to fully charge your battery.
The first step is "Bulk" where voltage is rising and current can be high (depending on the charger).
The next step is "Absorption" where the voltage will be held on a specific/defined level and the current will saturate the battery and will taper off until almost 0A. This phase is also called CV - constant voltage.
In the next step a good charger will start the "Float" phase, where the voltage of the full absorbed/saturated battery will be decreased to a lower level. This phase is not a strict must.
Definitely no equalisation.
Victron has preset lithium profiles which you modify for your battery. This takes care of most of it.
This graph looks strange... What type of battery is it? A 15S od 16S battery?
And is the current measurement correct with over 180A ? This is way too much for a 100Ah battery, and what kind of charger can provide that much at all?
@
jetlag Please check the image , this is voltage vs Current graph I think this is not as per standard.as current drops abruptly , data points are 5 minutes apart.
regards,
Boost is not equalization. Do not run an equalization cycle on lithium batteries. Please consult with your battery manufacturer regarding their recommended charging settings, as each manufacturer will have varying requirements for charging their batteries.
My AC Litium charger charges my 100 amp battery at 20 amps constantly while voltage rises and it never changes until battery is full , ie 80 amp hours takes almost exactly 4 hours . Never seen current decrease at all ever and voltage has never reached anywhere near the 29.2 volts that sown as charging voltage so i have no idea if its a good thing or a bad thing but charger was supplied by same company as battery , both Redodo ..
