Blog - Chargers and charging

16. Feb 2018
12V LP battery balancing and charging

Question:  Can I charge the 12V LFP battery using a conventional auto-moto charger 12V?

Answer:  With most of “cheap” car battery chargers you **cannot** charge the 12V LFP battery. Cheap chargers often end charging at 14V.  As a result the LFP batteries are not charged sufficiently. In order to charge to full you need to reach above 16V.

If you have an “advanced” manageable charger, it can be used provided you can set the charge level to at least 16V.

Simply said: you can charge with any kind of charger if you make sure that the battery voltage reaches at least 16V, but does not exceed the maximum limit of 17V.


Question: What are the experiences of balancing 12V batteries, when, for example, four pieces of 12V/40Ah in the series?

Answer: Unlike 3.2V cells that can hardly be operated without balancing, the 12V LP batteries behave “very sophisticated”, so the need for continuous balancing practically does not exist. It is just enough to check the voltage levels during inspection periods. If you notice a difference in the battery voltage levels, we recommend balancing all batteries manually to the same maximum charging level (ie, max 17 V / per battery).

Such manual balancing is made after recharging cells in series, connecting the single battery charger (for 17V) to each individual battery.

The inspection periods and manual balancing is recommended to be performed in these intervals (ie, after number of discharge / charge cycles):

* During the initial charge 
* After the first cycle 
* After the first 5 cycles 
* After the first 20 cycles 
* After the first 50 cycles 
* And then continue any time differences between batteries are noticed, about once every 50 to 200 cycles.


Question: How should new batteries 12V 20Ah, 40AH, 80 AH, 100 AH, etc. be formed before first usage?

Answer: The new 12V LP batteries delivered from the warehouse are partially charged. However before the first use, it is essential to charge the battery to full capacity. The initial charging should be done with the charging current set to less than 1C (typically 0.5C), till the voltage level of 17V is reached.

There is no other need for LP 12V batteries to be formatted or otherwise specially prepared for the use. After the first charge to full, the battery is ready to be used for use.

The above charging rule is also applied to the initial charge after the battery has been unused or stored for a long time. If not used more than 1 month, it is recommended to make again an initial charge to full.

Important: if you plan not to use the batteries for a long time, before storing you must charge batteries to full. In the case of storage longer than 1 year, it is required to recharge each battery after 12 months to full.

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