18650 Battery Packs, Built to Order

18650 packs built to order

An 18650 battery pack is specified from your device's voltage, capacity and space, then assembled from cells and a protection board matched to that configuration. We build packs from a single protected cell up to 48V-class strings, with each design written into a specification before production. Tell us the load profile and enclosure limits, and the specification is written around them.

18650 pack configurations we build

Series count sets the pack voltage and parallel count sets capacity. We build across the full span. At the bottom, 1S1P button-top packs run at 3.6V with a protection board on the pack, in several cell capacities. Two-series designs sit in the 7.4V class and serve industrial equipment. Three-series designs cover the 11.1V class, including industrial packs, patient-monitor packs and sickbed packs.

Above that, higher-series designs serve 24V, 36V (10S) and 48V (13S/14S) equipment. The same rules apply at every level: series and parallel counts are checked against your current profile and the physical space before the specification is written. If your device needs a format outside these classes, the configuration is still derived the same way, from the electrical requirement first.

For equipment that needs more capacity per cell, 21700 battery packs follow the same build process in a larger cell format.

Cells and grades: how cell choice changes capacity and discharge

The 18650 format is fixed; what changes between packs is the cell inside it. Capacity and discharge behaviour both come from the cell, so cell choice is a design decision, not a purchasing detail. A higher-capacity cell gives more runtime from the same parallel count, while a cell built for higher discharge delivers more current, usually at some cost in capacity per cell.

Cells can be selected from established cell makers — Panasonic, Samsung, LG, Molicel, Murata, EVE and BAK for lithium-ion; EVE and Great Power for LiFePO4.

Cell grade matters as much as brand. Starting from the required runtime, continuous discharge current and peak load, we select the cell and grade that meet all three, then set the parallel count to reach the target capacity. When a LiFePO4 chemistry suits the application, the same selection process applies within that list. If you already work to a preferred cell, say so at enquiry and the pack is specified around it.

Protection and BMS on 18650 packs

Every 18650 pack is fitted with a protection board or BMS matched to its configuration. The protection circuit is not an optional add-on: it is chosen together with the series and parallel counts, so the overcharge, over-discharge, overcurrent and short-circuit limits line up with the cells and the load.

For a small 1S1P pack, the board sits on the pack and protects a single cell group. As series count rises, the BMS manages more cell groups and the balancing and cutoff behaviour is set for that string. A 48V (13S/14S) pack therefore carries a different board from a 3S pack, and the specification records which one. This is what an 18650 battery pack with BMS means in practice: the board is part of the design from the start, not fitted afterwards.

BMS functions are confirmed in the project specification. Not every model carries every option, so the feature set for your pack is agreed in writing before production.

Examples from the range

The models below carry the range in concrete form, from the single-cell builds to the higher-series designs.

Each model in the single-cell range has its own product page with its full specification: the standard single-cell 18650 pack, the Samsung-celled single-cell 18650 pack, the Panasonic NCR18650BD single-cell 18650 pack and the Panasonic NCR18650GA single-cell 18650 pack. Two further references are the 11.1V-class industrial 18650 pack and the 7.4V-class industrial 18650 pack. Reviewing a build close to your requirement is the fastest way to settle a specification. If the closest match still differs from your device, the same platform is adapted rather than starting from nothing — our range of custom lithium ion packs is built on these designs.

UN38.3, IEC 62133 and MSDS documents can be confirmed and provided for specific models — tell us the model you are buying and we will confirm which documents cover it.

To start a specification, quote an 18650 pack with your voltage, capacity, load profile and space limits.

Frequently Asked Questions

Which cell brands and grades do you use for 18650 packs?

The cell brands we source for lithium-ion and LiFePO4 packs are covered in the cells and grades section above. Grade is selected against your runtime, continuous discharge current and peak load, and the chosen cell and grade are recorded in the project specification.

Can 18650 packs be built in 1S to 14S configurations?

Yes — from a single protected cell (1S1P) up to 48V-class strings (13S/14S), with the classes in between set out in the configuration section above. Series count sets voltage and parallel count sets capacity; both are checked against your current profile and available space before the specification is written.

Do you offer button-top 1S1P packs with protection board?

Yes. The 1S1P button-top pack with protection board is a standard build at 3.6V; the cell fitted sets the capacity, and each model's capacity is listed on its product page. The protection board is matched to the single-cell configuration, and its functions are confirmed in the project specification before production, since not every model carries every option.