Re-build an EZEE TORQ battery!

[richard ayres]

Hi everyone
I have a useful but old EZEE electric bike with two Li ion batteries both nearly dead! A new one would cost far more than I can afford. Surely it is possible just to replace the cells?
Li -ion cells are available on-line. Does anyone know what I need, how to do it and any things to avoid?
I currently have 36V 10AH batteries. I would like if possible to increase capacity at the same time.
I am not wedded to Li ion, but would like any new bits to fit the current battery case!
Any advice much appreciated!
Richard

 

[flecc]

Very difficult with this particular battery Richard, since it's cells are not side by side with strap connections but mounted vertically in columns. For space reasons, the D cells have to flat ended with no tags or end buttons, and I don't know of a source currently.

If you are able to get that type of cell, the equipment you need is a double end hammer head soldering iron and a length of angle iron with an end stop or similar to form a jig in which to create six columns of five cells in each.

Starting with the cell ends pre-tinned, the technique is to place two cells apart in the angle iron V, apply the hot double head iron while pushing the cells in on it, remove the iron and immediately slide the cells up against each other to solder together. Repeating this four times build the column of five cells.

Once six columns of five cells are created, they are bound into a rectangular stack of 2 x 3 columns.

Included in that pack is the thermistor mounted within a cell column to cell column space at the second cell from the top so that it measures the heat in the pack. You can recover and reuse the existing thermistor, wiring that and the pack as it was originally.

 

[flecc]

The above was for NiMh cells Richard, I misread your request. Others have found the eZee case too small to contain a replacement set of lithium cells with the correct BMS, and the existing BMS won't be suitable for today's cells which are very different and much better than the old ones. Most members with old Torqs have used a Li Ping LiFePO4 battery mounted on the rack, though one owner switched to SLAs.