{"id":7081,"date":"2021-06-24T01:04:48","date_gmt":"2021-06-24T01:04:48","guid":{"rendered":"https:\/\/notsealed.com\/?p=7081"},"modified":"2023-07-28T05:07:44","modified_gmt":"2023-07-28T05:07:44","slug":"e-bike-battery-problems-solutions-troubleshooting-guide","status":"publish","type":"post","link":"https:\/\/notsealed.com\/e-bike-battery-problems-solutions-troubleshooting-guide.html","title":{"rendered":"E-bike Battery Problems, Solutions, and Simple Troubleshooting Guide."},"content":{"rendered":"\n

In this post, we will be looking into how to take care of your e-bike battery, problems, solutions, and quick fixes. It’s a master electric bike troubleshooting guide that will keep your bike running at high capacity for longer.<\/p>\n\n\n\n

There is nothing worse than spending hundreds, or even thousands on an e-bike only to have issues with the internal lithium-ion battery or motor down the road.<\/p>\n\n\n\n

Ebike batteries are built tough but they are prone to fail prematurely if they are not taken care of. Just like any electrical components they need to be looked after.<\/p>\n\n\n\n

How to look after your e-bike battery<\/h2>\n\n\n
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Never charge your e-bike in direct sunlight. Heat will damage the lithium-ion batteries and could fry the charger. Always charge the battery in a cool well-ventilated area out of direct sunlight.<\/p>\n\n\n\n

Never fully deplete your e-bike battery. It is best to leave around a 10-20% charge in the battery pack. This will save the internal batteries from going into a low charge state preventing them from being recharged.<\/p>\n\n\n\n

Always charge your battery after every use. Lithium-ion batteries will over time lose charge so even if you are not using your e-bike it is best to charge it at least once a month.<\/p>\n\n\n\n

Never ride your e-bike through water, rivers, or deep puddles. Even though they are water resistant they may not be waterproof. Water ingress is an easy way to fry your e-bike speed controller, battery, or motor.<\/p>\n\n\n\n

How to test an E-bike battery?<\/h2>\n\n\n
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To test an ebike battery we need to first remove the battery pack from the e-bike. Make sure to turn off the power to the battery pack and unlock it prior to removal. Find the positive and negative main cable terminals which will be providing power to the electric motor.<\/p>\n\n\n\n

Put your multimeter on these terminals and check for 36-42V. Some battery packs will not output power unless a signal is sent to the BMS to start up.<\/p>\n\n\n\n

Most e-bike battery packs are plug and play which means they are easy to replace if they fail. They are hard to test and repair due to the complex design and tamper-proof screws.<\/p>\n\n\n\n

All quality ebike battery cells will be controlled by an electrical circuit called a battery management system<\/a> or BMS for short. This integrated circuit’s primary function is to charge and balance every 18650 lithium-ion cells in the pack to 100%.<\/p>\n\n\n\n

It will also manage a few other tasks like maximum power draw and over-temperature protection. In-built fuses will protect the battery pack if there is a short circuit.<\/p>\n\n\n\n

Now to test an e-bike battery we will need access to each individual cell. As they are wired in series and parallel it will be hard to test each one as they are all wrapped into place.<\/p>\n\n\n\n

After removing the plastic outer case you can use a multimeter set on DC volts to test each cell. You should get around 3 to 4.2V, any less and you could have a bad cell. Some 18650 battery cells are designed to go as low as 2v before the BMS cuts in but these are special lithium-ion cells. Most BMS will cut in around 2.5V<\/p>\n\n\n\n

If you find a 18650 battery cell that is under 2V it is best to replace the individual cell. Although I have successfully repaired some Ryobi 18v battery packs that won’t charge<\/a> so check out how this was done.<\/p>\n\n\n\n

How many 18650 for 36v<\/h3>\n\n\n\n

There are 10, 18650 batteries for 36v wired in series. For increased power and amps these 10-cell packs are then wired in parallel to complete a battery pack for e-bikes, lawnmowers, and other 36v devices. This will then make 30-40 18650 batteries depending on the application.<\/p>\n\n\n\n

My wifes Valk ladies electric bike<\/a> has 40 lithium-ion cells. So 10 are wired in series and there are 4 strings wired in parallel. The total power is 8.8Ah and each cell is 2200mAh.<\/p>\n\n\n\n

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