Home / Blog / E-bike battery specification

E-Bike · OEM Specification

E-Bike Battery Specification Checklist for OEM Projects

What to send, what can remain open, and what needs evidence before a battery is approved for the bike.

By Minglong Energy5 min read

A voltage and capacity target is a starting point, not a battery brief. To review an OEM project, a supplier also needs to know what the pack will power, where it must fit and how it will be charged.

You can begin the discussion with incomplete information. Send the documents you have and flag the decisions still open.

This guide is for OEM and sourcing teams, not consumer battery replacement or instructions for connecting unverified components.

Jump to checklist

Editorial concept illustration of a commuter e-bike with a frame-mounted blue battery and a separate, disconnected charger.
AI-generated concept illustration—not an actual Minglong product or a validated battery–charger combination.

Three details that a short specification can hide

Take “48 V, 20 Ah” as an example. Those two targets leave three questions unanswered: what does the controller demand, which charger is proposed, and can the pack be fitted and removed?

1. Which current does the controller specification mean?

Ask for the controller model, its battery-side limits, and the conditions behind any continuous or peak rating. An unexplained current figure can be misleading: Grin’s Phaserunner documentation lists battery-current and motor-phase-current limits separately. Do not use the phase-current limit as the battery’s discharge requirement. This example is not a controller recommendation. [1]

If only the motor’s rated power is available, leave the controller limits open. Dividing that power by nominal battery voltage does not establish the requirement: the motor’s mechanical output and battery input are different quantities. [2]

A distinction worth keepingTwo sides of the controller. Two different currents.
Battery
Battery-side
current
Controller
Motor-phase
current
Motor

Confirm the battery-side limits. Do not substitute a motor-phase-current rating.

Functional roles during motoring—not component locations, a wiring diagram or a rating recommendation. Based on Grin’s controller documentation.

2. Has a charging combination actually been identified?

Name the proposed charger and include its voltage, charging limits and interface information. These need to be reviewed with the battery requirements; matching-looking plugs are not evidence of compatibility.

UL Solutions addresses charger compatibility as part of the e-bike system. If the charger is undecided, mark it as open rather than simply writing “charger included”. [3]

3. Does “fits” include installation and removal?

An outline drawing may show where a battery sits without showing how it gets there. Include the mounting arrangement, latch or lock, connector access and removal direction—not just the enclosure dimensions.

Shimano’s battery-parts manual, for example, covers bracket alignment, latching and removal. Those instructions apply to the named models, not every e-bike. For your brief, the question is whether the pack can be installed, retained, connected and serviced in the intended frame. [4]

Describe the working day before fixing the capacity

Before settling on capacity, describe the ride: load, distance, gradients, assistance, speed and charging opportunities. Grin’s simulator explanation shows how weight, gradients and wind change system load. Nominal capacity alone is not a range result. [2]

Consider two planning examples. A delivery bike may make repeated loaded starts with little time between shifts; a commuter bike may need to cover a daily route before charging at home. Neither label, by itself, tells you which battery should be larger.

Also separate riding, charging and storage conditions. “Outdoor use” leaves too much unspecified; numerical limits belong in the technical review.

Ten inputs for a supplier-ready brief

Use the table to collect available information. It is a working brief, not a requirement to finish every decision before contacting a supplier.

Working checklistBring what you have. Mark the rest as open.

InputInformation to bringUseful supporting material
Vehicle and useBike type, load and intended working dayApplication brief or vehicle description
ControllerModel, battery-side voltage/current limits and peak conditionsController data and relevant settings
Range and duty cycleDistance target, route, assistance and charging opportunitiesRoute assumptions or available duty-cycle records
Mechanical integrationSpace, mounting, retention, connector access and removal pathDated drawing, model or preliminary envelope
ChargingIntended charger and charging arrangementCharger data and interface information
BMS and communicationRequired protection, status reporting and device interactionFunctional requirements and interface documents
EnvironmentRiding, charging and storage conditionsUse-environment description and proposed test scope
Target marketSales countries, vehicle category and responsible businessesMarket-specific documentation plan
ValidationWhat will be evaluated, by whom and against which conditionsAgreed test plan and acceptance criteria
Commercial lifecycleForecast volume, variants and service expectationsProject forecast and change-control expectations

This is an editorial planning framework, not a test standard, certification checklist or specification for a Minglong product.

Include volume and service expectations even before pricing is settled. Label forecasts as forecasts, and distinguish sample needs from possible production demand.

Keep unknowns visible—and give them a next step

An open item is useful when it tells someone what to do next. For each input, note its status, supporting document and version, unresolved question and next action.

For example:

An open item, made actionable

Illustrative brief entry—not a real customer case

Item

Controller battery-current limit

Open

Available information

Proposed controller model; detailed limits not yet supplied

Next action

Obtain the applicable controller documentation before confirming the pack’s discharge requirement

Notice that the next action asks for documentation; it does not assign a discharge rating before that information arrives.

Use states such as Target, Document supplied, Open and Verified for the agreed conditions. They are not a fixed sequence: a drawing can be supplied while its installation assumptions remain unresolved.

For “Verified,” record the evidence for the intended configuration and conditions. Receiving a datasheet is not the same as demonstrating a result.

A first discussion is not sample approval

At first contact, you are deciding what needs review and which information is missing. Before approving a sample for use, agree on the configuration, evaluation conditions, acceptance criteria and who will carry out each check.

Market-specific checks come into that decision. In Great Britain, OPSS guidance addresses compatible-charger information, environmental protection and technical evidence. It is not an exhaustive statement of legal duties or a global certification checklist. [5]

Final requirements depend on the vehicle, configuration, sales territory and responsible businesses. This guide helps prepare that discussion; it does not approve a battery, charger combination or route to market.

Start with the information you have

Minglong Energy accepts OEM and ODM battery project enquiries. Send the application, available system documents, target market and expected volume through the project form. Include the decisions that still need review.

Source review: 3 September 2026. This research-based guide draws on the manufacturer and regulatory materials linked above. The worksheet and illustrative entry are editorial tools, not customer case studies or measured performance results.

Sources & further reading

  1. Grin controller documentation
    ebikes.ca
  2. Grin technical explanation
    ebikes.ca
  3. UL system-safety explanation
    www.ul.com
  4. Shimano dealer’s manual, installation section
    si.shimano.com
  5. OPSS guidance
    www.gov.uk

Prepared and maintained by Minglong Energy.

Back to top