BatteryBlocs Assembly Guide

Congratulations on your purchase of BatteryBlocs.  Now you can build a modular, repairable, rebuildable battery using only common hand tools.  Geek out, brothers and sisters!

 1.  Put Cells in Cases

When building a battery the parallel groups are assembled first.  Assembling in parallel means that the positive and negatives of all cells are connected.  A 6P1S Bloc holds 6 cells in parallel and gives you six times the amp hours of one cell, but the same voltage.  So six 2600 mah (thousands of an amp, also 2.6 amps) cells in parallel will be 6 X 2.6 for 15.6 amp hours.

Identify the positive and negative terminals of your 18650 cells. The negative terminals are flat, the positive have a small raised disc. If unsure check with a volt meter.

Grab a black case. Be sure that there is only one magnet in each hole of the magnet retainer. Center the magnet retainer in the plastic case. Fill the case with the 18650 cells, the negative side of the battery going into the black cases. The magnets will snap the cells in place.  The cap should fit loosely and have some wiggle room at this stage.

Grab a red case. Check the magnets, only one for each cell. Center the magnet retainer.  Place the red case on the tops of the 18650 cells already in the black case. The neodymium magnets will aid in alignment and will hold the case together until the nylon compression bolts are installed.  Look for the alignment arrows, they need to face the same way on both the black and the red cases.

Assemble the remaining BatteryBlocs, leaving the bolts out for now.

Split Cases.  A split case holds cell both in parallel and in series.  so, a 6P2S holds 12 cells in total.  There are two parallel groups of 6 connected in series.  Cells are inserted right side up and upside down according to directions on split case BatteryBlocs.

2.  Assemble Blocs into a Battery

Now we connect the parallel groups into series to multiply the voltage.  A 6P10S battery will have 10 parallel groups of cells connected in series, which is positive to negative etc, to multiply the voltage.  So a 6P10S battery built of lithium cobalt cells at 3.6 nominal volts would have 10X3.6 = 36 volts.  Using the above example, if built from 2600 mah cells it would have 15.6 amp hours.  So, a 36 volt, 15.6 amp hour battery.  The watt hours is volts times amps for 36volts X 15.6 amp hours equals 561 watt hours or .5 kwh.  An ebike burning 100 watts could cruise four hours on this battery.  Video on Series/Parallel.

Place the assembled Blocs into the desired battery configuration using the red and black to identify the positive and negative terminals. For serial wiring, multiplying voltage, the pattern will be red, black, red, black, etc. For parallel wiring, multiplying amperage,  blacks and reds will be together not alternating.

For Split Packs extra care is needed.  Assemble with full attention to the cells positive and negative positions.  If there are any sparks, pull the Bloc apart.  Wait a minute after the top is placed on and feel the batteries.  If you feel them getting warm you have miss-assembled them.  Pull the case apart and fix your mistake.

To connect the series wiring place the metal piece with 4 holes across two BatteryBlocs lining up the holes.(Except the 4P which has just one hole) You can move the underlying magnetic retainer plate a little to align the series connectors. Insert nylon bolts. Each bolt has a washer on each side.  When assembling split packs be sure NOT to bridge the gap on the magnetic retainer with a steel washer.  If you do you will see sparks and you will have shorted the battery.  

To be efficient, you could also attach a ring terminal at this time. The ring terminal must make direct contact with the magnetic retainer plate.  The positive terminal get a large wire ring.  The negative terminal gets a large and a small wire ring.  Every positive on the battery gets a small wire ring terminal. 

So, a 6P10S battery would have 2 large wire rings, one on the positive and negative, and 11 small wire rings, one on each positive and one on the negative.  

Tighten the nuts finger tight. Repeat until all series connections have been made.  Check your battery packs voltage to be sure you got it right.    Now tighten the nylon nuts.  If you overtighten they will make a snapping noise.  The magnetic retainer plate may bend slightly, this is OK as it is acting like a spring to keep pressure on the magnets.

3.  Provide Structural Support

Run ¼ inch threaded rods through the top tubes if desired. Use nuts to secure. Do not use washers if installing inside a plastic fence post- they won’t fit.    Get them finger tight for now.

4.  Wire the Balance and Power Wires

Secure the sensor and power wires to the BatteryBlocs by crimping or soldering to the ring terminals. If you did not install the ring terminals while assembling the battery, just loosen the nuts and bolts to install.  Do not solder the power (large) ring terminals while attached to the battery. Crimp, or remove and then solder.

How to wire a BMS video.

Wiring for a Hobby Charger.

5.  Tighten the nylon nuts

Now that the battery has been properly wired tighten up the nylon bolts.   The official maximum torque for these nylon bolts is 19 foot lbs, but 15 is plenty. A Dewalt screw gun with an adjustable clutch makes short accurate work of it. Many people simply tighten by feel, it’s not critical.  The nylon bolts are somewhat elastic and the steel can flex a little.

If you overtighten they will make a snapping noise.  The magnetic retainer plate may bend slightly, this is OK as it is acting like a spring to keep pressure on the magnets.

 Check your battery packs voltage to be sure you got it right.

When finished tightening, the cells should have zero up and down movement, but should be able to be rotated with friction.  IF you used threaded rod now tighten up the nuts on the ends.   Because the caps have a little wiggle room, tightening the threaded rod will not disturb the electrical connection.  Your battery pack should now be structurally quite rigid.

Any questions at all contact me at [email protected]

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