Parallel Charging 52v Batteries

Posted by ENTroPicGirl@reddit | ebikes | View on Reddit | 8 comments

I have two identical batteries bought at the same time; 52v 50amp 10Ah Mini-Max from Electrify Bikes Co., and am going to connect them via ‘Y’ connectors in parallel. Connecting them in parallel is easy, just charge them within .1v<.5v of each other and I’m good to connect. However I’m not sure how to go about charging.

Do I:

Option A:

Disconnect one black lead in the charging dongle to Battery 1 and the red lead on charging dongle to battery 2.

This is how we charge deep cycle 12v batteries using a battery tenders in the RV (shown in image)

Option B: hook charging dongles 1 & 2 together and connect that to charger.

Second question: my charger has a dial that says 80% 90% 100%. Which setting do I choose? The goal is to have them last as long as possible. Speed at which they charge isn’t my concern.

Third question: how often should I charge my batteries, do I wait till I’m down to one bar of power or should I charge when I’m at 50% trying to make these batteries last as long as possible.

Build Spec:

-Bike : Borealis ‘Flume’

-Wheel sizes: 29x2.6 (for late spring/summer/fall) and 26x5 Johnny 5 for spring mud season 26x5 studded Dillinger fives for winter

-Motor: CYC X1 Gen4 52v

-Batteries: 52v 50amp 10Ah Mini-Max Electrify Bikes Co.