Battery case dimensions, measured

Measured openings, cell ceilings and fitments for every ALX empty e-bike battery case — 110 models, one table. Pick by cells, not by listing text: a mould listed at 91 cells holds 91 of 18650 and fewer of the fatter 21700.

110 models up to 200 × 18650 / 160 × 21700 81 measured openings MOQ 1 piece

Cell counts are the maximum the mould accepts in that format — not a recommendation. The same mould holds fewer 21700 than 18650 because each cell is fatter. Fitment and material are as moulded; voltage follows the cell count you build to (10S = 36 V, 13S = 48 V). Jump to a series: Hailong · Silver Fish · Integrated · Downtube · Rear Rack · Water Bottle.

Hailong battery cases (15)

Model	Max 18650	Max 21700	Opening	Section	Fitment	Material
ALX019A	52	30	Opening 170 mm	—	—	ABS
ALX019B	52	30	—	—	—	ABS
ALX053B	78	—	—	—	Mounting centres 73 / 73 / 162.19 mm	ABS + PC
ALX053C	—	—	—	—	—	—
ALX068	52	30	—	—	Mounting centres 171.61 / 70.5 / 65.75 mm	ABS
ALX082	91	52	—	—	Charge port DC1.2 / DC2.5 / 3-pin microphone or video	ABS
ALX085	—	—	—	—	—	—
ALX096	52	30	—	—	Mounting centres 171.61 / 73 / 73 mm	ABS
ALX097	—	—	—	—	—	—
ALX097B	—	52	Opening 396 mm	—	Mounting centres 73 / 73 mm	ABS
ALX098	65	40	—	—	Mounting centres 171.61 / 73 / 73 mm	ABS
ALX146	65	40	—	—	Mounting centres 171.1 / 57 / 57 mm	ABS
ALX149A	104	70	—	—	Mounting centres 161.15 / 71.9 / 72.1 mm	ABS
ALX149B	117	80	—	—	Mounting centres 161.15 / 71.9 / 72.1 mm	ABS
ALX149D	—	—	—	—	—	—

Silver Fish battery cases (27)

Model	Max 18650	Max 21700	Opening	Section	Fitment	Material
ALX021	130	—	Opening 265 / 325 mm	—	—	ABS
ALX027	—	—	Opening 155 / 172 mm	—	—	ABS + aluminium alloy
ALX035	—	—	—	—	—	ABS
ALX035B	65	52	Opening 285 mm	—	—	—
ALX036	130	—	Opening 265 / 325 mm	—	—	ABS
ALX038	100	—	Opening 285 / 325 mm	—	—	ABS + aluminium alloy
ALX040	65	52	Opening 285 mm	—	—	ABS
ALX042B	100	—	Opening 285 mm	—	—	ABS
ALX050	104	—	—	—	—	ABS + aluminium alloy
ALX051	104	—	Opening 285 mm	—	—	—
ALX057	104	—	Opening 160 / 285 mm	—	—	ABS
ALX061	130	91	Opening 265 / 380 mm	—	—	ABS
ALX061B	—	—	—	—	—	ABS + PC
ALX063	130	91	Opening 160 / 265 mm	—	—	ABS
ALX072	100	—	Opening 285 / 325 mm	—	—	ABS
ALX072B	100	—	Opening 285 / 325 mm	—	—	ABS + aluminium alloy
ALX075	78	—	Opening 285 / 325 mm	—	—	—
ALX076B	—	—	—	—	—	—
ALX080	65	39	Opening 285 / 325 mm	—	—	ABS
ALX113	—	—	Opening 150 / 160 mm	—	—	ABS + aluminium alloy
ALX113B	—	—	Opening 160 / 173 mm	—	—	—
ALX129	—	—	Opening 156 / 160 mm	—	—	—
ALX134	—	—	Opening 192 mm	—	—	—
ALX136	—	—	Opening 173 / 189 mm	—	—	—
ALX136D	—	160	Opening 189 / 380 mm	—	—	—
ALX144	—	—	Opening 160 mm	—	—	—
ALX181	—	—	Opening 530 mm	—	—	—

Integrated battery cases (28)

Model	Max 18650	Max 21700	Opening	Section	Fitment	Material
ALX003	40	—	Opening 305 mm	Battery box 88 × 47 mm	—	Aluminium alloy
ALX006	52	26	Opening 305 / 345 mm	Battery box 102.2 × 60.2 mm	Frame tube 109 × 67 mm	ABS
ALX009	75	—	Opening 345 mm	Battery box 114.2 × 58 mm	Frame tube 121 × 65 mm	ABS
ALX011	40	—	Opening 280 / 290 mm	Battery box 88 × 40 mm	Frame tube 94.8 × 47 mm	ABS
ALX014	40	—	Opening 280 / 290 mm	Battery box 88 × 40 mm	Frame tube 94.8 × 47 mm	ABS
ALX015	52	26	Opening 305 / 345 mm	—	—	—
ALX017	65	—	Opening 305 / 345 mm	—	—	—
ALX029	52	26	Opening 305 / 345 mm	—	—	—
ALX055	65	—	Opening 305 mm	—	—	—
ALX056	65	—	Opening 305 / 345 mm	Battery box 102.2 × 60.2 mm	Frame tube 109 × 67 mm	ABS
ALX060	65	—	Opening 305 / 345 mm	Battery box 102.2 × 60.2 mm	Frame tube 109 × 67 mm	Aluminium alloy
ALX060B	—	—	Opening 405 mm	—	—	—
ALX076	—	20	—	—	End cap 71.44 × 22.5 mm	ABS
ALX079	52	40	Opening 345 / 370 mm	Battery box 93.4 × 60 mm	Frame tube 100 × 66.8 mm	ABS
ALX084	52	40	Opening 345 / 370 mm	Battery box 93.4 × 60 mm	Frame tube 100 × 66.8 mm	ABS
ALX090	52	—	—	—	—	—
ALX095	30	—	Opening 285 / 350 mm	Battery box 64.83 × 43.7 mm	Frame tube 90 × 53.07 mm	Aluminium alloy
ALX106	78	52	Opening 345 / 370 mm	Battery box 110 × 67.8 mm	Frame tube 117 × 74.8 mm	ABS + PC
ALX107	52	26	Opening 305 / 345 mm	Battery box 102.2 × 43 mm	Frame tube 109 × 50 mm	ABS + PC
ALX108	78	52	Opening 345 / 370 mm	Battery box 110 × 67.8 mm	Frame tube 117 × 74.8 mm	Aluminium alloy
ALX108B	78	56	Opening 345 / 370 mm	—	—	—
ALX108C	—	—	Opening 380 mm	—	—	—
ALX110B	104	80	Opening 380 mm	—	—	—
ALX122	78	52	Opening 345 / 370 mm	—	—	—
ALX122B	78	56	Opening 345 / 370 mm	—	—	—
ALX124	52	30	Opening 305 / 345 mm	Battery box 102.2 × 43 mm	Frame tube 109 × 50 mm	ABS
ALX131	78	52	Opening 345 / 370 mm	Battery box 110 × 67.8 mm	Frame tube 117 × 74.8 mm	ABS
ALX161	30	—	Opening 227 / 310 mm	—	—	—

Downtube battery cases (21)

Model	Max 18650	Max 21700	Opening	Section	Fitment	Material
ALX030	65	40	Opening 355 / 415 / 465 mm (18650) · 435 mm (21700)	—	Downtube	ABS
ALX030B	65	40	Opening 355 mm	—	—	—
ALX030D	65	40	Opening 355 / 415 / 465 mm (18650) · 435 mm (21700)	—	Downtube	—
ALX058	65	28	Opening 365 / 465 / 515 mm (18650) · 414 mm (21700)	—	Downtube	—
ALX077B	78	52	Opening 382 / 462 / 538 mm (18650) · 392 / 482 mm (21700)	—	Downtube	—
ALX086	65	—	Opening 370 / 500 mm	—	Downtube	—
ALX089	52	—	Opening 420 mm	—	Downtube	—
ALX099	78	52	Opening 355 / 425 / 445 mm (18650) · 425 / 450 mm (21700)	—	Downtube	—
ALX099B	—	—	—	—	—	—
ALX100	78	80	—	—	Downtube	—
ALX100A	78	52	Opening 355 mm	—	—	—
ALX118B	68	—	Opening 472 mm	—	—	—
ALX119A	65	—	Opening 340 / 391 mm	—	Downtube	—
ALX127	104	65	Opening 382 / 462 / 498 mm	—	Downtube	—
ALX139	108	100	Opening 449 mm	—	—	—
ALX143	52	—	Opening 278 mm	—	Downtube	—
ALX148B	—	—	Opening 182 mm	—	Downtube	—
ALX158	52	20	Opening 355 mm	—	—	—
ALX163B	78	65	Opening 360 mm	—	—	—
ALX173	30	30	Opening 364 / 432 mm	—	—	—
ALX178	200	160	Opening 445 mm	—	—	—

Rear Rack battery cases (17)

Model	Max 18650	Max 21700	Opening	Section	Fitment	Material
ALX032	60	52	—	—	Rear Rack	—
ALX033	—	—	Opening 160 mm	—	Rear Rack	—
ALX048	—	—	Opening 165 mm	—	Rear Rack	—
ALX065	—	—	Opening 172 mm	—	Rear Rack	—
ALX069	60	52	—	—	Rear Rack	—
ALX069B	65	40	—	—	Rear Rack	—
ALX078	52	40	—	—	Rear Rack	—
ALX094	—	—	Opening 150 / 155 mm	—	Rear Rack	—
ALX102B	—	—	—	—	—	—
ALX103	—	—	Opening 170 / 174 mm	—	Rear Rack	—
ALX114A	65	52	—	—	Rear Rack	—
ALX114B	65	52	Opening 275 / 335 mm	—	Rear Rack	—
ALX128	—	—	—	—	Rear Rack	—
ALX137	—	—	—	—	—	—
ALX165	80	52	Opening 290 mm	—	—	—
ALX166A	104	—	Opening 166 mm	—	Rear Rack	—
ALX166B	104	78	Opening 164 mm	—	Rear Rack	—

Water Bottle battery cases (2)

Model	Max 18650	Max 21700	Opening	Section	Fitment	Material
ALX054	52	—	Opening 215 / 280 mm	—	Water Bottle	—
ALX105	30	30	Opening 319 mm	—	Water Bottle	—

Common questions

What are the standard dimensions of an e-bike battery case?

There is no single standard — a Hailong-class case opens around 90 mm high while a rear-rack case opens around 110 mm, and lengths run from 180 mm to 400 mm depending on cell count. 81 of our 110 models list a measured opening and section above; the rest are confirmed per order.

How many cells fit in the largest ALX battery case?

200 cells on 18650 and 160 on 21700. Cell count is a ceiling, not a recommendation: leave room for the BMS — a 13S BMS is longer than the 10S one most cases were moulded around, and it is the usual reason a build will not close.

Can I get a dimensional drawing before ordering?

Yes. Every model on this site has a drawing with the internal envelope, mounting centres and cable-exit positions. Send your frame's internal dimensions and we check the fit against the mould before you commit — quoted within five hours.

Next step

Found your size? Confirm the fit against your frame

Send the frame envelope and the configuration you are building to. Quoted within five hours, MOQ one piece.

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