I have this LTO Titanate battery. 81v at the moment. How to connect this to Multiplus 2 48/5000 ?
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I have this LTO Titanate battery. 81v at the moment. How to connect this to Multiplus 2 48/5000 ?
you will need to carefully dismantle some of the interconnects.
make sure that the max cell voltage X number of cells in series is < max input voltage of inverter charger (~62V?). Unfortunately this will leave you with some un-used cells as there are not enough to make 2 strings of 48V,
The MultiPlus 48 works between 38V and 66V, so if the batteries are discharged with 81V it might be enough for two parallel packs (40V each). Voltages can then be configured on the MultiPlus.
You will also need a BMS that monitors the cells individually, lithium batteries never charge equally, and if a cell is over charged or over discharged it will be damaged permanently.
How many cells i connect and what is charger settings? I do not know exactly battery capacity. 12-15ah cell.6 cells is connected parallel 6P. If i connect to Multiplus 25S6P. Sry my english but i think people understand. :)
LTO cells can be charged at maximum 2.7V.
But better do not go over 2.6V cell voltage (or even 2.5V, especially if you do not use a BMS).
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When discharging, do not discharge them under 2V (cell voltage).
Be very careful to not go under 2V LTO cell voltage, because below 2V the LTO cell voltage drops very fast when discharging. A safer limit would be 2.1V when discharging.
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For a 48V (nominal) battery, you need 21 or 22 LTO cells in series.
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Before connecting them in series, you should equalize the cells to all be at the same charge level (either fully discharged or fully charged, depending on if you will use or not a BMS).
If you won't use a BMS - equalize the cells when empty.
If using a BMS - equalize the cells when fully charged.
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