Custom 700wh extender pack

[michael.kozera]

hi there.

just wanted to share what i made, as i was fairly disappointed with most / all bottle extenders on the market, as they are all way to small "wh's" and physically too large for the wh's they give.

So i made, IMO, probably the smallest 700wh extender pack you can physically make. fits inside of a standard water bottle cage. its abit long but hey, it fits.

specs are:
52v bms (30a)
56x LG-mj1 (3500mah) arranged in 14s4p = 705.6wh
weight is approx 3kg
100% waterproof

i can use this in all of my ebikes to extend the range. i can also use it in my solar battery box or my homes solar battery, and even my protable solar battery inverter.

outside plug is the output.

inside plug is the input

about the same roudness as a standard water bottle, just alot taller

i really like using it in my BBSHD intense 951 hyper ebike as it takes the standard battery of 1,600wh and turns it into 2,300wh's!!!

as for my custom carbon ebike which has an custom internal battery of 700wh, this extender pack makes it 1,400wh's of pure fun.

the only downside to this extender is that the cells are packed tight, and there is little to no protection if i was to ever drop the batt and/or puncture it. probably the reason why so many extenders on the market are very large.... to protect them from damage.

 

[thaeber]

Did You put a protection circuit in the battery, to indicate different voltage levels in between built in battery and extender pack? Or do You always plug both batteries in, fully charged?

 

[michael.kozera]

Did You put a protection circuit in the battery, to indicate different voltage levels in between built in battery and extender pack? Or do You always plug both batteries in, fully charged?

depends. i usually use this battery as a AUX batt. as in i will usually start by using this battery first, once done ill unplug and flip the switch on the bike to use the bike battery to avoid any back feeding.

however, i have tried running both batteries at once, and after the initial 10-20w feed-back which usually last a few mins, the batteries stabilize and i can run them together till dead.

it has a bms, so does the bike. but no one way diodes.