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Lifepo4 what type of charger do i get

4K views 7 replies 5 participants last post by  evnz 
#1 ·
I am looking at getting lithium batteries and was told they use a diferant charger than lead acid can anyone please tell me what type to get please
Thanks owen
 
#2 ·
A typical LiFePo4 charger is CC, CV. That means it charges at a constant current until it reaches a specific voltage, then holds that voltage until the current drops to a certain level, completing the charge.

The primary differences to lead charging is that lead will take less amps, and often terminates with a very high voltage gassing phase.
 
#5 ·
Do you have a car yet? What motor and what controller are you using? I will assume that all three packs are connected as a single string of lithium batteries for a 144 volt system. Being that I'd go with a 144 volt charger that can pump out a reasonable amount of amps for charging. The Elcon is a good choice. Others use different ones but the Elcon is pretty specific for each pack size so if you do get one you will only be able to charge your 144 volt pack. If you later decide to upgrade then you will have to get a different charger. But 144 volts is good.

Pete :)
 
#7 ·
I am looking at getting lithium batteries and was told they use a [different] charger than lead acid
Actually a CCCV charger is ideal for both lead acid and for Li-ion.

That's because the intelligence to charge your Li-ion battery resides within your BMS, not within your charger. The BMS will ensure that the charger stops before ANY individual cell is overcharged. Then, after the BMS has balanced the pack a bit, it will allow the charger to come back on, and charge the battery a bit further. At the last cycle, the battery will be top balanced, and the charger will then be able to go to the CV (Constant Voltage) mode, and finish charging the battery. For a detailed discussion of how that works, see this video.

Ironically, chargers with a "Li-ion profile" are not as good as a plain old CCCV charger. because A) they give you the wrong impression that they will protect your battery during charging (they don't), and B) they may stop before the battery is full, even if the BMS says it's OK to charge some more.

So:
1) Select a good BMS
2) Get a plain old CCCV charger
 
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