Cheap Victron LiFePO4 Lithium Battery 12.8V/60Ah – Smart

Victron LiFePO4 Lithium Battery 12.8V/60Ah – Smart, 3 year warranty. 

• With integrated cell balancing
• Can be parallel and series connected
• Bluetooth app available to monitor cell voltage and temperature

Why lithium-iron-phosphate?

Lithium-iron-phosphate (LiFePO4 or LFP) is the safest of the mainstream li-ion battery types. The nominal voltage of a LFP cell is 3,2V (lead-acid: 2V/cell). A 12,8V LFP battery therefore consists of 4 cells connected in series; and a 25,6V battery consists of 8 cells connected in series.

Rugged:

A lead-acid battery will fail prematurely due to sulfation:

• If it operates in deficit mode during long periods of time (i.e. if the battery is rarely, or never at all, fully charged).
• If it is left partially charged or worse, fully discharged (yacht or mobile home during wintertime).

A LFP battery does not need to be fully charged. Service life even slightly improves in case of partial charge instead of a full charge. This is a major advantage of LFP compared to lead-acid. Other advantages are the wide operating temperature range, excellent cycling performance, low internal resistance and high efficiency.
LFP is therefore the chemistry of choice for very demanding applications.

Efficient:

In several applications (especially off-grid solar and/or wind), energy efficiency can be of crucial importance. The round trip energy efficiency (discharge from 100% to 0% and back to 100% charged) of the average leadacid battery is 80%. The round trip energy efficiency of a LFP battery is 92%. The charge process of lead-acid batteries becomes particularly inefficient when the 80% state of charge has been reached, resulting in efficiencies of 50% or even less in solar systems where several days of reserve energy is required (battery operating in 70% to 100% charged state). In contrast, a LFP battery will still achieve 90% efficiency under shallow discharge conditions.

Size and weight:

Saves up to 70% in space
Saves up to 70% in weight

Expensive?

LFP batteries are expensive when compared to lead-acid. But in demanding applications, the high initial cost will be more than compensated by longer service life, superior reliability and excellent efficiency.

Bluetooth:

With Bluetooth cell voltages, temperature and alarm status can be monitored.
Very useful to localize a (potential) problem, such as cell imbalance.

Victron LFP batteries have integrated cell balancing and cell monitoring. Up to 5 batteries can be paralleled and up to four batteries can be series connected,so that a 48V battery bank of up to 1500Ah can be assembled. The cell balancing/monitoring cables can be daisychained and must be connected to a Battery Management System (BMS).

Battery Management System (BMS):

The BMS will:

1. Disconnect or shut down the load whenever the voltage of a battery cell decreases to less than 2,5V.
2. Stop the charging process whenever the voltage of a battery cell increases to more than 4,2V.
3. Shut down the system whenever the temperature of a cell exceeds 50°C.