Power Tank

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The Zero's Power Tank is the only available battery upgrade for the SDS Platform that is officially supported or has a straightforward path to install.

  • It's equivalent to a single Power Pack Module for a Zero FX/FXS.
  • A "3-brick" or "longbrick" S or DS model can accept the Power Tank as an upgrade.
  • It has its own internal BMS which requires a significant amount of behavioral parity and configuration matching with the bike's Power Pack.
    Officially, the BMS firmware versions must be exactly matched, but this is not confirmed.
  • The MBB is wired and configured to talk to two BMSs total, #0 for the Power Pack and #1 for the Power Tank.
    This corresponds to handling two BMSs for each X platform module.
    Power Tank logs and settings will be accessible as BMS #1.
Dealership Install Requirement
An install requires dealership access to:
  • Check and match firmware revisions between the Power Tank, Power Pack, and MBB.
  • Connect the systems safely so that there isn't a major current inrush that damages the bike or the Power Tank.
The Power Tank and Power Pack products are revised per generation of Cells. The Power Tank adds 25% capacity to the main pack.
  1. 2.8kWh (discontinued) original version released 2014.
  2. 3.3kWh (discontinued), released 2016.
  3. 3.6kWh, released 2018, listed for 2014+ models.
Install Limitations
Only one Power Tank may be installed per vehicle.
  • The S Platform tank area is the only reasonable place to mount a Power Tank, because of its incredible density.
  • The MBB is configured to coordinate and communicate with two BMS units.
  • The Main Pack has one BMS on the S Platform, and the X Platform is set up to carry one or two Power Pack units, each with a BMS, unless using a Long Brick (2017+).
It is not set up for disconnect without dealership involvement.
Part numbers
Part number Part Price (USD)
12-08011 Power Tank Fasteners and Harness Kit
It fits in the tank area for 2014+ Zero models of S/DS/SR/DSR under the tank plastics.
2014+ frame features are required for the approved mount.
  • A carrier tray in the tank area suspends the Power Tank almost a centimeter total (3mm gap clearance) above the main Power Pack battery.
  • Holes in the frame on the forward inner sides of the tank area anchor the Power Tank.
    These holes typically are covered by cable runs, and can be found by moving them aside.
    J-bolts hook into these holes and retain a corner bracket around the top rear edge of the Power Tank.
Operational Notes
Cell balancing seems less effective than and separate from the main power pack per cell balance with powertank?.
9.5 x 7.5 x 9.75in (HxWxL)
24 x 19 x 25cm
Early installations (2014) of the Power Tank had issues where the Power Tank's capacity would not count towards the bike's capacity, or the bike might shut down.
General consensus appears to be that charging a bike with the Power Tank (prior to some BMS firmware revision) could cause a self-protective disconnection due to imbalances between the Power Tank and the main Power Pack.
While this shouldn't happen with 2015+ Power Tanks, they can still have issues during or after installation if the Power Tank's charge state is not matched / balanced with the main Power Pack.
Basically, one or other contactor might not shut, resulting in reduced power capacity.
If for any reason something like this occurs, plug the bike in and wait for pack voltage and power tank voltages to match. The bike should operate normally at that point.
A cable harness attaches to the Power Tank's rear-facing output port.
The harness hooks into the bike's main systems to communicate with the MBB, and also runs to the B+ and B- terminals on the controller to deliver power to the motor.
Pre-2014 models also have an incompatible interconnect harness, much like their accessory charging circuit is lower capacity.
A 2013 model with the battery recall applied might support the connection harness, but the MBB will likely not interface with it.
Warning Warning: Only connect or disconnect this cable while the main contactor is open and the motorcycle is fully de-energized. Connecting a Power Tank with any circuits powered could damage or disable the vehicle entirely.
General guidance before connecting or disconnecting any high-powered electrical systems from a Zero:
Wait a full 10 minutes to be absolutely sure that components have discharged fully, but 2 minutes is typically safe.
Confirm this with a DC voltmeter.

The Power Tank has its own BMS and contactor and coordinates with other bike systems via the MBB.

The contactor limits are presumably the same as for the main Power Pack contactor limits, except that the current/power input limit would be ¼ of the Power Pack.

The Ah rating of the Power Tank should be displayed on it just to understand what the current basis for 1C is.