I sold electric bike replacement batteries for about the last 9 years
But I don't sell any now
It's unfortunate that not many electric bike shops do sell replacement batteries
Until there is a supply of batteries at a reasonable price
I now advise anyone wanting an electric bike battery to get one from China direct
To do that go to www.aliexpress.com register and search "36v 10AH Li-ion e-bike battery"
There are many shops there selling all types of batteries
The most common battery in e-bikes in Australia is the upright-under-the-seat type
(the Chinese call these "silverfish" )
European and US e-bike batteries have a variety of other shapes
Recently they are using cells with smaller diameter and with these there can be more AH within any case
You can fit enough to have 12AH or 15AH in the same case as your (typical) 10AH battery
This means that if you want to travel further on a single charge you can get a 12 or 15 AH battery
but the cost is almost in proportion to AH
The usual output is 4 (2 effective) slots at bottom
If you have an older type such as "computer" pug at top you ought to change it, it probably being illegal
but they will make battery with that socket if you ask
A battery will come with the male prongs that fit into the slots under the battery
The power wires from this can be joined to the power wires going to the controller...
Usually by opening the controller case. A pair of electrical connectors may be required
A new charger will come with battery, so matching input is no problem
Most shops send freight included to anywhere in Australia
Prices are in $US so allow about 1/3 more for exchange rate plus about 3% addon by the bank
The sellers are "verified" so there is some protection against the shitty batteries which
which have been too often sent to Australia
At least go there and see the prices before looking local
ONE THING TO WATCH
If your new battery seems completely dead when you put in place and turn it on
DO NOT PANIC
Most probably the battery is fine, but has a different POLARITY to the previous one
The remedy is simple. The plug with 4 prongs needs be turned 180 degrees.
ELECTRIC BICYCLE BATTERY INFORMATION
(For more information about electric bicycle batteries, and how to look after them
LITHIUM ION BATTERIES
There are various kinds of "lithium ion" battery.
There is some confusion about just what batteries are "lithium ion" or "li-ion".
You can refer to wikipedia for more information but most commonly "li-ion" batteries are those with lithium, manganese and/or cobalt oxide (LiMnO2, LMN, LiMnCo)
and "LFP" batteries are those with Lithium Iron Phosphate, or LiFePO4 (although LFP is also a "lithium ion")
Most lithium batteries are "li-ion". "LFP" batteries are less common.
This is not because "li-ion" batteries are better. They are not.
The battery makers in China have been making "Li-ion" batteries and don't want to change production lines
for smaller quantity of "LFP" batteries. Similarly the bike assemblers do not want to change
LFP batteries are about 20% more expensive but have some worthwhile advantages over Li-ion batteries.
You can read a lot about these batteries elsewhere but the main advantages are
* much longer life - twice, or more, recharges compared with "Li-ion"
* much greater stability and resistance to vibration, heat and shock
* very much less risk of combustion or fire if damaged
LFP batteries are exchangable for li-ion batteries but have slightly higher voltage and do need their different charger.
Li-ion chargers have 42v charging voltage, and LFP chargers have 43.8v
(If you are not sure of your battery type, see under side of charger. The small print will tell you the "Output Voltage")
Both types of charger are available separately
There are different shapes and sizes of Lithium battery and
batteries of similar shape and appearance can have different input and output sockets, and different fixing in place and locking.
Common sockets are shown below.
One other difference you may see is battery "polarity". Affects batteries with output slots at bottom. Up till now all my batteries had
positive (+) on left. Now I am seeing some batteries with positive on right side. It is easy to change, by reversing the slots at bottom of
the battery or the prongs on top of controller. The controller will not accept current going the wrong way.
The various types of battery are :
* Batteries that fit within the frame under the seat
These have various profiles. A metal case with 70mm by 110mm profile with round indent at front and sliding rail at rear is common. ("tall" - Chinese call these "silverfish")
can have different height. Before replacing one of these Check the height of the locking pin.
Power outlet at top was common but now power outlet at bottom is common.
It is usually a simple modification to replace the power outlet.
The male socket can usually be added above controller box.
* Batteries that sit on or within a rack above back wheel
Most commonly the battery and rack are designed to fit one another. To keep a rack and replace battery you need to confirm the dimensions, the sliding plate, locking pin position. Otherwise you will need a battery and rack combination.
These can be added to most bikes, and are often part of a conversion kit
* Batteries that attach to seat post
These can be added to most bikes. You need room beneath the seat and a round seat post.
* Batteries that attach to the down tube ("bottle batteries") or sit within the "V" above pedal
These can be added to most "triangle" frames with straight tubes.
* Batteries that fit within the frame tube (some folding bikes)
* Batteries that fit within a wheel (attached to axle and inside a case)
Some e-bike brands have a proprietory shape, size, etc battery and only batteries made for those bikes can replace.
Many smaller brands of e-bikes have batteries that are more generic that can be replaced, albeit with some minor alteration.
To replace a battery you should first ask the shop that sold the bike for a replacement cost, and whether one is available.
If not you will have to look for one, or a similar one that may need a minor modification. Of course there are many suppliers on E-Bay,
but try and see if they have a shop with stock in Australia (or your country).
Beware that many of them will just pass on your order to Hong Kong or China. In which case, you may as well import one directly yourself.
Some suppliers in China that I know will send retail (one off) batteries are www.goldenmotor.com and www.leafmotor.com
SEALED LEAD ACID SLA BATTERIES
If you need to replace an SLA battery first consider getting a Li-ion battery and adapting that to fit.
36 volt Li-ion or LFP for 36 volt SLA (etc). The voltages are very similar and motor will work the same,
but do get a new charger with the new battery.
The LFP battery will be much smaller and have different fixing but in many cases it can be done.
It would be easier to adapt one with the same output socket, but the 3 pin output socket will be harder to find,
because that socket on a battery is an illegal fitting.
The shop that originally sold the bike may have a complete battery case and batteries. Quite likely they will not have one.
If you prefer to keep using the SLA battery then keep the case because it fits and locks in place.
Take the 2 halves apart (screws at each corner) and take out the 2,3 or 4 12v batteries inside.
Note how key lock and fuse (if there is one) are connected. Cut the last connecting wires where they join the battery terminal.
(not the ones connecting battery to battery). Replace with matching new 12v batteries (available where car batteries are sold) and
connect up wiring as the battery was before by soldering. Make sure the solder on the tabs is solidly joined.