When it comes to connecting high power batteries to drive systems on your ebike there really is only one viable option. Anderson Powerpole connectors come in 4 main power ranges, the 15 amp, 30 amp, 45 amp and much larger 50+ amp connectors. For almost all applications I recommend getting the 45 amp connectors as the price difference is negligible and it’s better to have the higher amperage connectors even when running at lower power levels. The Anderson has a sacrificial tongue which will take the brunt of the spark that will inevitably be created every time you hook up your high power battery.
When using Anderson connectors I usually run the wiring on 10 gauge multi-stranded speaker wire (red/black is my favorite). Although 10 gauge is far more than what you need at most power levels, it means you have lower voltage drop and the cable will not heat up. It also means that the insulation will tend to be a little thicker than the lighter gauge wiring, and I like to have stiff wires that don’t flop all over the place.
The Anderson Powerpole connectors come in a wide range of colors, but I recommend red and black for power and then yellow, green and blue for the phase wires just so you’re standardized on the same colors as everyone else. To correctly connect the Powerpole connectors you will need a set of good crimpers. It’s well worth investing $30 for a set of decent crimpers from ebay, I usually buy from connectorpros although there are many vendors for this product.
Crimping the 45 amp connectors is a snap. Just strip off about 7-8 mm of insulation then put the metal connector in the jaws of the crimper into the slot that matches the amp rating stamped on the die. Push the connector in till it stops and then carefully feed the wire into the connector till the insulation hits the metal connector. Then ratchet the tool all the way down and release. Although you can probably crimp these connectors with a standard wire crimper/stripper, I strongly recommend getting the dedicated Powerpole crimpers. They pay for themselves quickly in the amount of frustration they will save you. I am not crazy about the 30 amp connectors, so if you are crimping very fine wires use the 45 Amp connectors and crimp them on the 30 or 15 amp slots as appropriate on the crimpers. This will ensure that they won’t pull out even when crimping on super thin wires.
Safety Note: Never cut through both the power and ground connectors at the same time on your battery. Only work with one side at a time, never have both ends stripped and loose as you might accidentally hit both at the same time with the crimpers if you are not careful. Cut and strip the wire, crimp the connector, then put the plastic housing on it before you start on the other wire. This almost guarantees no fireworks when working on battery connectors.
Once the metal connector is crimped on the wire you must push it into the connector with the tongue side down and push it all the way in till it clicks. If it doesn’t click then it’s not all the way in and can pull out. The connectors fit side by side like legos sliding together and becoming a single connector.
The Roll Pin
There is also a roll pin which gets inserted into the circular hole between the connectors which keeps the connectors from sliding back and forth in relation to each other. This is handy for making a single connector out of multiple connections. If you want the connector to hold tight no matter how hard the wire gets pulled you can use a ziptie or velcro-one ties between the two wires to go around both connectors to keep it from loosening up. If you want to detach it you can cut the ziptie or release the velcro.
The larger 50+ amp connectors are more challenging as they need to be soldered rather than crimped. I hold the connector cup side up and fill it with hot solder then stick the wire in before it cools and let the solder solidify around the wire. This technique works quite well, at least as well as crimping a connector would, although some people then crimp the soldered connector to make doubly sure it will not fail. Give the wire a pull after the solder hardens to make sure it is attached good and tight.
Silicone and heat-shrink tube the connectors
One thing I have done which seems to make the connector a little more waterproof and a lot more sturdy is to put a dab of silicone where the insulation meets the connector then slip some heat shrink tubing over the plastic connector and wire and shrink it down while the silicone is still wet. This makes a much stiffer connector that is less likely to break off or have water and snow seep in.
SPEC-Pak Weather resistant snap together housings
Although I have not tried them, my good friend Larry at Boxy Bikes really likes them, especially in the winter. To bunch 4 Anderson connectors together and protect them from the elements you can buy the 4 Pole SPEC-Pak. Be aware that it requires a separate tool to install these connectors and they are rated for 1000 volts which is far more than you would ever want to use on an ebike. They are also kind of pricey compared to the normal connectors.
Where to buy
There are reputable online dealers with web stores like powerwerx.com . That being said I usually buy mine on ebay from connectorpros. Like everything on ebay there are always cheap Chinese knockoffs so if you don’t go with a reputable vendor you may get a sub-standard product.
The electrical connectors form the foundation of your ebike build. Without them your bike won’t move. It is quite frustrating trying to deal with loose or bad connectors. I have yet to find any connector that is as inexpensive, works as well and is as easy to install as the Anderson Powerpoles.