Technical specification of cells
Recommended initial and subsequent charging is to 3.65 V.
Nominal capacity of the cells is 400Ah
The minimum voltage is 2.5 V.
Maximum discharge current is 3C continously.
Operating temperature -45°C up to 85°C (discharging)
These battery cells are suitable for all traction applications including electric vehicles. Fully complies also for stationary applications - such as energy storage.
There is no Selfdischarging effect.
Can be recharged at any state of discharge - no memory effect
LiFePO4 is a very safe technology, not spontaneous combustion, does not react with moisture or with oxygen.
All cells are supplied new directly from the manufacturer.
|Please read USER MANUAL before use.|
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Size of pack
8 cells, 24V
Total capacity 9.6 kWh / Depth 520 mm / Weight 108 kg
LiFePO4 in various projects, in depth
LiFePO4 cells and batteries are very versatile. Can be used as starting battery, is ideal for Energy storage, back up battery or to power your boat or caravan.
For most frequent 12V use, in boats, caravans or campervans check our quick guide with connection diagrams showing how to upgrade battery or install new one.
Why LiFePO4 over LeadAcid
Discharge test of SLA vs. LiFePO4 batteries
Winston LiFeYPO4 technology outperforms conventional AGM,SLA in several aspects.
They work longer (lifetime, cycle-life), our 10 years experience shown avarage lifespan of 5000 cycles (depending on the discharge rates, minimum 2000, maximum observed 8000).
More poweful, with available continious discharge rate at 3C (3 times its capacity), LiFeYPO4 provide more energy than AGM,SLA.
No acids, unlike AGM,SLA the LiFePO4 does not contain life threathening substances.
Non explosive, Li-Pol (Polymer) and other batteries frequently used in consumer electronic (Phones, Tablets) are extremely dangerous when physically damaged or misused. You can actually pierce LiFePO4 with metal and not cause fire or explosion. Shortcut it for long periods with the same (little to none) effect.
Initial, first time charging
Cells are precharged from manufacturer to conservation charge (usually 30-50%).
The cells have to be charged with low current before the first use.
The first charge should not exceed 0.5 C - eg for 400Ah cell is 200A.
FAQ: Initial charging information
For initial charging of multiple cells, connect them in parallel and the charger outputs should be connected to both ends of the parallel rows of cells, exactly as it is described here:
FAQ: The initial charging of the number of cells
We recommend to use chargers specially made for LiFePO4 cells First charge and initial balancing of the whole pack is important step towards long lifetime.
Alternatively you can use regulated (Laboratory) Power supply as initial charge tool. Short description how to proceed.
Balancing and protection
Demonstration video of BMS123 Smart assembly
BMS123 Smart connection demonstration including Charger, Appliance and the ever important fuses and switches.
Circuit diagram of the BMS123 Smart with power relays and current sensors
Power relays generally have higher separate consumption. With a basic connection, the charging relay remains connected even when the load relay is switched off, and in some circumstances it could still discharge the battery. As an example, this can be avoided by blocking the charging relay via a load relay auxiliary switch contact, in combination with a parallel switch for forced charging. Similarly, possible back consumption on of the battery charger may be blocked at its output. We generally recommend using a coil optimizer relay or 123 Smart Dual Relay.
Connecting the cells
Winston produce cells with easy to assemble square shape, terminals are made for screws allowing simple installation with spanner.
Interconnection between cells is important part of any battery pack. Original copper connectors are made of several thin layers for ideal flexibility and conductivity.
Make sure to clean oxidation from both, terminals and connectors (with Sandpaper or similar) before assembly. Oxided contacts may have very high resistance and cause unbalancing of the battery.
Plastic caps are cheap solution to prevent unwanted shortcuts and for easy plus and minus marking (red and black colors are available).
Demonstration video of cell assembly
|Nominal Voltage (V)||12|
|Max discharge current (A)||1200|
|Optimal discharge current (A)||200|
|Max charging current (A)||1200|
|Optimal charging current (A)||200|