BLACK TEA MOTORBIKES Bonfire S Battery 101 Electric Bike Instruction Manual

: June 5, 2024
: BLACK TEA MOTORBIKES

Table of Contents

How To Read your Display
Range & Life
Good To Know
Charging
Battery Balancing
Maintenance of the Battery
Temperature & Storage
Maintenance of the Charger
Contact and Support
References
Read User Manual Online (PDF format)
Download This Manual (PDF format)

BLACK TEA MOTORBIKES Bonfire S Battery 101 Electric Bike Instruction Manual

How To Read your Display

It is easy to see how much battery power (charge voltage) you have at any given time by looking at your LCD Speedometer dashboard display. Read below for more information about these display readings.

Display

The LCD Display shows the current real-time battery voltage in the upper right corner of the screen. This is your best battery state of charge (SOC) indicator. The battery’s voltage reading changes while riding based on the battery’s power demand and power input from regenerative braking. At lower states of charge, the Controller (ECU) of will limit power output to prevent damage to the battery. To further protect the battery, your Bonfire S will stop riding at 44 V & the Bonfire X at 88 V.

NOTE: The internal Voltage reading of the display is not 100 % accurate which means your display shows the actual voltage with an accuracy of ± 0.4 Volts.

The LCD Display shows a visual representation of the battery charge level in roughly 10% increments in the lower right corner. Use this as an indicator to know generally how much energy you have left. When the battery is close to being fully depleted, the last bar will begin to flash, warning you to charge the battery as soon as possible.

Range & Life

Each battery gives the bikes an expected range of between 20 to 50 km on a single charge depending on the mode you use, the terrain, and your size/weight. All of these things affect your overall range. For example you can increase your range by using the regenerative braking to conserve battery power.

For the Bonfire S you can expect following range:
Speed: 50 km
Normal: 60 km
Eco: 70km

For the Bonfire X you can expect this range with two batteries:
Speed: 50 km
Normal: 60 km
Eco: 70km

NOTE: Even though the Bonfire X has two batteries, the range is lower because the Bonfire X consumes more energy. The upside is you accelerate faster and have a higher top speed.

Battery Life

This depends on several factors, including the age of the battery, the frequency of your discharge/recharge cycles, temperatures, and general storage techniques. Your battery will typically give most riders an average of 5 years of awesome riding adventures or approximately 800 full discharge/charge cycles!

Good To Know

Battery Sag
Become familiar with the amount of battery sag full throttle causes in eco mode, normal mode, and sports mode. Sag is described as the amount of electricity drawn depending on how much throttle is given. On a colder day it is common at full throttle for the voltage sag to be 6 volts and on warmer days 4 volts. Each mode limits the amount of sag. ECO has the lowest Sag while SPORT has the highest voltage sag. That is why ECO mode will help prevent cut offs by reducing the sag amount.

NOTE: Due to the “Voltage Sag”, your 10% bar display will show a lower SOC than prevails in the vehicle. Therefore, we recommend reading the volt display when the vehicle is at rest (for example, while waiting at a traffic light) and using the table in chapter 1.1. to derive the true SOC.

Battery Cut Off

When the amount of battery sag falls below 42 V (84 V for the Bonfire X), your Bike will turn off. Cut off occurs because the battery management system is programmed to protect the batteries from damage from low voltage.

Depending on the weather, riding behavior and the balancing of your cells, your Bonfire might cut off earlier. To avoid this, here are a few tips:

Make sure that your battery cells are well balanced (more later)
Use ECO mode when your SOC is below 20 % or use your throttle gentle
Check on your display that your voltage does not drop below 43 V (86 V) when you accelerate or ride at high speeds
Store your battery at home if the ambient temperature is below 10°C. A warmer battery cuts off later and has a smaller voltage sag

Low Battery Levels

Your Bonfire battery does not discharge in a straight constant line, it is more like a curve where the top of the charge above 85% (56 V or 102 V) and the charge below 15% (45 V or 100 V) deplete faster

If your battery is well balanced then it will cut out at 43 V (86 V). If the battery is unbalanced, it can cut out at 45 volts (90 V) or below, depending on the degree in different voltages between the individual cells.

Charging

A simple equation is used to quickly calculate how long a given battery charger will charge a particular battery from fully discharged to fully charged. Here is the basic equation:

For example, with the standard 35 Ah battery charging on the 10A charger, the total charge time is 3.5 hours. However, while the equation gives a good general idea of how long it can take, actual battery charging times vary depending on various factors related to your battery including the battery’s age, SoC, internal and ambient temperature.

Best Practices For Charging

It is really easy to charge your Bonfire. The battery pack in your is removable, which allows to you remove and take the battery with you to charge or store the battery to prevent theft. However, you can charge the battery with it installed in the bike.

The battery is a flammable lithium-ion battery and should not be stored or charged near a heat source or open flame. For more safety precautions, reference our user manual on our website: https://blackteamotorbikes.com/pages/service

Follow these instructions for battery charging:

Place the charger on an open (uncovered), flat, cool, dry and secure surface so that it will not be disturbed or heated while charging the battery.
Leave your battery ON to charge.
Plug the charger input plug into a suitable power outlet (before plugging the charger into the battery). The indicator light on the charger should be green with nothing connected to it. The charger works on 110/220 V 50/60 Hz standard home AC power outlets.
Connect the charge cable to the battery. After the battery is connected, the charger light will change from GREEN to RED to indicate that it is charging. When the Battery is fully charged the light will change to GREEN.
If the indicator light is not lit at all, it is possible that the charger’s replaceable fuse may be blown and needs to be changed. Do NOT open the charger case. Replacement fuses are included in the charger box. Fuses are easily replaceable without removing the charger case/cover!

Battery Balancing

Unbalanced batteries when fully charged will show on the display between 55.6 V and 56.5 V (111 V – 113 V). They will also cut out sooner as high as 48 V (96 V) rather than at 43 V (87 V). A simple way to tell how unbalanced your battery is by intentionally trying to make it cut out (but we do not recommend it).

Battery balancing serves the purpose of equalizing the voltage between all 168 individual battery cells inside a battery. When a battery is balanced, 100 % of its capacity is available, whereas an unbalanced battery provides less than 100 % of its capacity and causes premature battery degradation. Balancing the battery is a slow process and is achieved at low milliampere values.

With the Black Tea Motorbikes charger, your battery will be automatically balanced during the last hour of the charge. The balancing starts when the battery cell voltage is at 4.17 V and stops at max 4.2 V. The current is very small at 30 mA.

Maintenance of the Battery

A great thing about lithium-ion batteries is they have little to no “memory effect.” This means that you can charge your battery after each ride, regardless of its charge level, with little effect on its long term health. Each battery has a built-in smart Battery Management System (BMS) that monitors the health of the cells, and our optimized battery chargers automatically monitor and turn off when the battery is fully charged.

Below are some additional battery charging tips, advisories, and notes that can be handy to keep in mind…

COOL DOWN – After riding your Bonfire, do not charge the battery yet, let it cool down for an hour or more if possible. It is best to provide your battery a cooling period of about 1 hour AFTER a ride before starting to charge it, and then let the battery rest for about 1 hour after charging it before going on a ride.
It may not always be practical, but charging the battery to 80% and discharging it to 20% are actually best for a long life. It’s of course more than OK to charge it to 100%.
Keep in mind that the maximum charge voltage is 58.5 Volts ± 2% (117 Volts ± 2%). Yours may charge fully to a little more or a little less. This normal, so don’t worry if it is not exactly at 100 %. Also note that the bike draws a certain amount of voltage (up to 0.4 Volts) when it is on.
Try not to let the battery sit at 100% on the charger longer than necessary.
Only use a battery charger provided by Black Tea Motorbikes. Using an aftermarket chargers can damage your battery and will void your warranty.
Avoid constant exposure to extreme temperatures for a long battery life.
Avoid frequently fully discharging your battery to 0 % in order to prolong the life of the cells.
The chargers from Black Tea Motorbikes charge quickly up to 80%, and then they taper off. This is normal but good for your battery. So, the last 20% will take longer to finish but don’t worry.
After charging the battery, let the battery rest for an hour if possible so that the battery can cool down and to let the cell charges can even out. This is known as cell balancing. When new, battery cell balancing can take a couple or more 100% charge cycles to completely balance out.
Always unplug the battery or remove the battery when cleaning or working on the bike, especially when any covers are removed!
Avoid damaging the connector, and keep it clear of debris. If it get sdirty, carefully clean it using compressed air or a soft bristle nylon brush if available.
DO NOT charge or use a damaged battery.
DO NOT drop the battery.
DO NOT disassemble the battery.
DO NOT immerse the battery in water and prevent it from getting wet.
DO NOT short circuit the positive (red) and negative (black) terminals of the connector.
DO NOT try to charge your battery when it is frozen. This can lead to permanent damage. Let your battery rest indoors and warm up to room temperature before charging.

Temperature & Storage

Using and storing your battery in extreme heat and extreme cold are not ideal for your battery. Below are some lists of considerations with respect to the Lithium Ion battery pack.

Temperature

If possible, make sure that the battery is kept above 10°C and below 40°C to avoid performance issues. If it is colder than 15°C outside, bring the battery inside with you. Cold storage will result in more voltage sag, which is felt as a lack of power
Never leave the battery fully discharged in cold weather for a long time. Always keep a minimum 30- 50% state of charge.
Never charge the battery if the battery itself is below 10°C.
Never try to rapidly heat up a frozen battery. Let the battery come up to proper temperature slowly and naturally.
When you ride in the cold, you could lose range, sometimes as much as 20%
Cold riding could also result in early voltage cutoff. This means your Bonfire could turn off earlier than expected.
When you start riding a cold Battery, give your Bonfire 10 minutes to heat up. After 10 minutes the whole electric drivetrain (battery, controller & motor) should reach a higher temperature where they function more efficiently. So, try to keep it low for the first 10 minutes.
Lithium-ion batteries perform well at elevated temperatures up to 40°C but prolonged exposure to heat reduces longevity.
Don’t charge the battery if it is above 45° C.
If possible, don’t charge the battery right after riding since cells can be above 45° C.
If possible, don’t charge the battery in direct sunlight if the ambient temperature is + 30°C). Charge in a cool place away from direct sunlight

Long Term Battery Storage

For seasonal riders here are some ways to help best preserve your battery:

Don’t store the pack fully charged. Store your pack at around a 40-50% charge level
Store your battery in a dry place at room temperature.
If storing the battery IN the bike, make sure that you unplug your battery from the controller by disconnecting the battery connector.
Do not leave the battery and charger connected together and plugged to the wall outlet to keep the battery charged.
If you let the battery go too low for too long, the battery could potentially suffer permanent damage, and that is not covered under your warranty.
Failure to follow proper charging and storage procedures may result in a non-functional battery, and replacement will not be covered under warranty.

Maintenance of the Charger

Battery chargers generally require little to no maintenance. However, below are some basic tips for maintaining your battery charger for optimal function and life.

Do not just toss your battery charger around or store it haphazardly.
Keep water and other liquids away from the battery charger at all times.
Keep the cooling fan uncovered so that the charger is able to properly keep itself cool.
Periodically wipe the case of the battery charger with a soft cloth to remove dirt/debris.
Store the battery charger indoors in a safe place.
Always keep a spare battery charger fuse handy in case it the fuse blows.