E-Bike Battery Packs: 48V LiFePO4 and Replacements

DIDIDEDE supplies e-bike battery packs to distributors, fleet operators and workshops: replacement packs for bikes already in service, higher-capacity upgrades, and wholesale builds for our own e-bike range.

Most enquiries come down to three numbers – voltage, capacity and how much current the controller pulls. Get those right and the pack will work; get them wrong and no amount of capacity helps.

Key takeaways

  • Three numbers decide an e-bike pack: voltage, which must match the controller; capacity in amp-hours, which sets range and can be increased freely; and the controller’s continuous and peak current.
  • 36V suits entry-level and urban bikes with 250 W hub motors; 48V is the mainstream choice for 250-750 W systems and runs cooler, because higher voltage means lower current for the same power.
  • A 48V 31Ah pack holds about 1,483 Wh – roughly 60-90 km per charge at a realistic 15-25 Wh per kilometre, depending on assist level, rider weight, terrain and tyres.
  • Sizing by duty: 400-600 Wh for a 10-20 km urban commute, 700-1,000 Wh for 30-50 km daily riding, 1,400 Wh and up for delivery and cargo work, plus 20-30% headroom in cold climates.
  • LiFePO4 gives more charge cycles and better thermal stability at the cost of weight; NMC is lighter and suits performance builds where range per kilogram matters.

Choosing the right e-bike battery: voltage and capacity

  • 36V – entry-level and urban bikes, typically with 250 W hub motors. Cheaper, and enough for flat commutes.
  • 48V – the mainstream choice for 250-750 W systems. Higher voltage means lower current for the same power, so the pack and controller run cooler.
  • Capacity in Ah sets the range. A 48V 31Ah pack holds about 1483 Wh; at a realistic 15-25 Wh per km that is roughly 60-90 km per charge, depending on assist level, rider weight, terrain and tyres.

Before ordering, check the controller’s continuous and peak current rating and the connector type. Capacity can go up freely – voltage cannot.

If you are weighing 48V against 72V, our 48V vs 72V battery comparison covers what changes in range, current draw and component cost.

E-bike battery packs we supply

Replacement or upgrade: what to check before you buy

  • Voltage must match the controller. Never fit a higher nominal voltage pack to a system rated for less.
  • Capacity (Ah) can be increased for more range, as long as the pack physically fits and the charger is correct.
  • Connector and pin-out. Send a photo if you are unsure; we supply common e-bike connectors and can build to yours.
  • Mounting format – downtube, rear rack or integrated frame.
  • BMS current rating must exceed the controller’s peak draw, or the pack will cut out on acceleration.
  • Charger – match the chemistry (LiFePO4 charges to a different voltage than NMC).

Working out what you actually need — voltage class, watt-hours, continuous current and the datasheet numbers that decide it — is covered in our battery resources, including how to size a pack and how to read a specification sheet.

LiFePO4 or NMC for an e-bike?

LiFePO4 gives more charge cycles, better thermal stability and a longer service life, at the cost of extra weight for the same capacity. NMC is lighter and more energy-dense, which suits performance builds where range per kilogram matters. We build both, and we supply the cells separately if you assemble your own packs.

How many watt-hours do you actually need?

Work backwards from the ride, not from the price list:

  • Short urban commute (10-20 km/day) – 400-600 Wh is plenty, and it keeps the bike light and cheap.
  • Daily commuting (30-50 km/day) – 700-1000 Wh, which is where most 48V 15-20Ah packs sit.
  • Delivery and cargo duty – 1400 Wh and up, plus a pack that can sustain the current without getting hot. Our 48V 40Ah build (1.92 kWh) is the usual answer here.
  • Cold climates – add 20-30% headroom. Lithium cells deliver less capacity below freezing and cannot be charged below 0 deg C without a low-temperature charge function.

There is a worked method for this, including the margins for cold weather and ageing: how to size a battery pack turns range or runtime into watt-hours and then into amp-hours at your voltage.

Care, charging and safety

  • Use the charger supplied or specified for the pack – LiFePO4 and NMC have different charge voltage profiles.
  • Charge between roughly 10 deg C and 45 deg C, and never charge a frozen pack.
  • For long storage, leave the pack around 50-60% state of charge in a cool, dry place.
  • Check the housing, connector and cable strain relief periodically on fleet bikes.
  • Do not open or bypass the BMS – the protection circuits are what keep a damaged pack from becoming a fire.

The same rules apply on a larger scale once you are holding stock. Lithium battery storage and charging safety covers warehouse zones, storage state of charge, charging areas and what actually works on a lithium fire.

Wholesale, replacement programmes and OEM

If you run a fleet, a workshop or a distribution brand, we build to your specification: capacity, connector, housing, communication protocol and labelling. Minimum order quantity is 3 units for prototypes and samples, and a sample takes about two weeks – see the custom battery pack OEM process and our battery pack manufacturing capability.

A replacement programme generates failed packs, and those are regulated waste. Lithium battery recycling and end-of-life compliance sets out who carries the obligation, how waste packs must be shipped, and what to agree with your supplier in advance.

Frequently asked questions

Can I fit a 48V pack on a 36V bike?

No – the controller and motor are rated for a nominal voltage. Fit the same nominal voltage and increase capacity (Ah) instead if you want more range.

How long does an e-bike battery last?

A LiFePO4 pack is typically rated for around 2000 cycles to 70-80% of original capacity. In practice, storage temperature and how deeply you discharge matter as much as the cycle count.

Can I use a higher capacity pack than the original?

Yes, if it fits the mount and the charger is correct. More Ah means more range and usually a longer life, because each cycle is shallower.

Do you ship batteries to my country?

Yes. Packs travel as class 9 dangerous goods with UN38.3 test summary, MSDS, CE and IEC 62133 documentation, by sea, air or rail.

Can you put our brand on the packs?

Yes – housing, labelling and packaging can carry your brand on OEM runs. Tell us the quantity and we will quote.

Get a quote for e-bike batteries

Send the voltage, capacity, connector and quantity. Request a quote, or message us on WhatsApp.

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