November 20, 20232 yr To be picky the least stressful is "top up if needed, use it, charge it partly" (on a timer) because aging takes off exponentially in the region above 4V and the BMS can kill a battery stored close to empty. And balance occasionally. There's more to it than how long your battery lasts, it doesn't croak at 300 to 500 cycles, it just has 20% less capacity. If your commute needs 48V x 10Ah you'd buy 12Ah to get 4 years of use, 14 Ah to get 8 years. My batteries are 11 years old, a bit down on range and maximum current but still ample. 480Wh x 400 cycles is ~ 10 miles per working day for 8 years, similar life to a crankset. A moderately oversized battery reduces the C rate for charge and discharge improving its life further, compounding the benefit and reducing e-waste. You've reserve for longer trips, cold weather, ageing and upgrade to a more powerful controller. And that occasional balancing: it optimises capacity but if you've spare capacity... "2. When you charge to 80%, your motor will make 20% less power all the time you're using it." 20% less power at the limit, but mostly the usual power for 80% of the range. With a torque sensor system the rider will push "a bit" harder and get 2 or 3 bits more assistance, similarly with a throttle or PAS settings.
November 20, 20232 yr To be picky the least stressful is "top up if needed, use it, charge it partly" (on a timer) because aging takes off exponentially in the region above 4V and the BMS can kill a battery stored close to empty. And balance occasionally. There's more to it than how long your battery lasts, it doesn't croak at 300 to 500 cycles, it just has 20% less capacity. If your commute needs 48V x 10Ah you'd buy 12Ah to get 4 years of use, 14 Ah to get 8 years. My batteries are 11 years old, a bit down on range and maximum current but still ample. 480Wh x 400 cycles is ~ 10 miles per working day for 8 years, similar life to a crankset. A moderately oversized battery reduces the C rate for charge and discharge improving its life further, compounding the benefit and reducing e-waste. You've reserve for longer trips, cold weather, ageing and upgrade to a more powerful controller. And that occasional balancing: it optimises capacity but if you've spare capacity... "2. When you charge to 80%, your motor will make 20% less power all the time you're using it." 20% less power at the limit, but mostly the usual power for 80% of the range. With a torque sensor system the rider will push "a bit" harder and get 2 or 3 bits more assistance, similarly with a throttle or PAS settings. Let's change it to the maximum power you can get from the motor will always be 20% lower than what it would have been if you had charged it to 100%.
November 20, 20232 yr Author Guys I would say that getting into scientific research about battery life is not that necessary. In the end of the day the battery will last atleast 3-5 years, same as a car battery. It is a consumable that must be taken in consideration. I think I made a good choice as they are here on the market and I have 2 years warranty I can benefit from. Prefer them than any other Chinese crap that's on Ebay and Amazon and they have great customer service. 1000 1500 charge cycles on a 1000 or 1500 W motor with 20AH battery would give me atleast 10-15,000 Miles. Waiting for the product will follow up with images of the package!
November 20, 20232 yr Guys I would say that getting into scientific research about battery life is not that necessary. In the end of the day the battery will last atleast 3-5 years, same as a car battery. It is a consumable that must be taken in consideration. I think I made a good choice as they are here on the market and I have 2 years warranty I can benefit from. Prefer them than any other Chinese crap that's on Ebay and Amazon and they have great customer service. 1000 1500 charge cycles on a 1000 or 1500 W motor with 20AH battery would give me atleast 10-15,000 Miles. Waiting for the product will follow up with images of the package! Battery costs about 2-3p per mile then! Not too bad.
November 20, 20232 yr TLDR: get an oversize battery to help the planet, your wallet and your enjoyment of your bike. Let's change it to the maximum power you can get from the motor will always be 20% lower than what it would have been if you had charged it to 100%. A 48V battery charges from 42V to 54V or thereabouts, or to 51.6V if charged to 80%, so the average voltage during use is 95%. Back emf can account for half of that so very roughly when you need maximum power you'd climb up to 10% slower, on steep climbs you'd have 100%. Edited November 20, 20232 yr by AntonyC
November 21, 20232 yr I thought I'd better check the above and... it's official: Charging to 80% makes this G310 hub motor 0.5mph slower on climbs: See the settings
November 21, 20232 yr I thought I'd better check the above and... it's official: Charging to 80% makes this G310 hub motor 0.5mph slower on climbs: [ATTACH type=full" alt="55190]55190[/ATTACH] See the settings Thata's academic because there's no sensible reason to do it.
Join the conversation
You are posting as a guest. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.