Go Back  Bike Forums > Bike Forums > Electric Bikes
Reload this Page >

When to Re-Charge Battery to Maximize Its Life?

Notices
Electric Bikes Here's a place to discuss ebikes, from home grown to high-tech.

When to Re-Charge Battery to Maximize Its Life?

Old 03-20-22, 12:11 PM
  #1  
newbert
Senior Member
Thread Starter
 
Join Date: Aug 2013
Posts: 55
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 11 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
When to Re-Charge Battery to Maximize Its Life?

I just got an e-trike and this whole electric thing is new to me. I'd like to establish a best practice for maximizing the battery's life and am seeking advice on when and how often to re-charge the battery.

For example, I just finished my first ride on the trike and battery level was at 80% when I finished. Should I re-charge the battery now? Or should I wait until it reaches a level of __%? (Fill in the blank). I re-charge my phone every night no matter what the remaining charge level is, but I'm not sure whether the same should be done with an e-bike battery.

Any insight on this question would be appreciated. Thanks.
Bert
newbert is offline  
Old 03-20-22, 01:20 PM
  #2  
mclewis1
Member
 
Join Date: Dec 2020
Posts: 42
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 8 Post(s)
Liked 28 Times in 20 Posts
The following applies to common commercial Li-ion batteries used on most ebikes, trikes, scooters, etc. The guidelines for other chemistries (LFP for example) can be a little different.
a) don't constantly charge to 100%, 80-90% will maximize lifespan (this also includes phones and such but that's a different conversation that depends on brands and phone features). If you really need the full capacity (for full range) go ahead and charge to 100% but use the battery soon after (hours, not days), so just don't leave a fully charged battery sitting around. Most commercial batteries have a BMS that will also balance individual cells which helps with their overall lifespan. This usually occurs when the battery reaches 100% so it would good to occasionally to bring the charge to 100%. An example of all of this is to simply recharge daily or every few days to 80% and maybe taking the battery from 80 to 100% for special (Sunday) long rides. If you don't end up charging to 100% for a month or two then it would be a good idea to do so before one of your rides.
b) don't deplete a battery below 20%. Most BMS and/or ebike controllers won't allow you to go below a specific voltage which equates to something just above 20%.
c) don't charge a battery that's below 32F/0C, and if possible bring a battery up well above freezing before charging (so bringing it inside and letting it come to room temp is a good idea before charging)
d) it doesn't really matter for the lifespan if you charge from 20-30% or 50-60%, just do it under reasonable conditions.
e) if you are going to store a bike for a while (or just not ride for a month or so) the battery should be charged to about 50% or so, and occasionally monitored to ensure it hasn't gone below 20% on it's own (which shouldn't occur for a battery that's in reasonable condition).

To figure out what condition a battery is actually in you need to monitor it's actual voltage (so a multi meter or other measuring device is needed, and not just the bars on the battery or your display). Then with some experience with the battery and your charger you can get an idea of how long it takes to go from empty (typically 20-30%) and 50% or 90% or whatever. There are good tables online for various batteries (36. 48, 52v, etc.) that will give you an idea of what voltage applies to percentages. These tables are for theoretical batteries, so the characteristics of your particular battery may differ a little bit. This is why it's good to monitor your battery and get to know it (how fast it drops from full charged, how low your BMS will allow your battery to drop to, etc.).

None of these numbers (well maybe except for the 100% stuff ) are exact, they're just ballpark guidelines. The most important (IMHO) guideline is however to just not obsess or worry about your battery. Get to know it, get an idea of how it performs, how your charger performs, how your control/display shows the various states of charge, and just don't abuse it.

Last edited by mclewis1; 03-21-22 at 08:47 PM.
mclewis1 is offline  
Likes For mclewis1:
Old 03-20-22, 07:34 PM
  #3  
2old
Senior Member
 
Join Date: Jul 2014
Location: socal
Posts: 3,422
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 678 Post(s)
Liked 466 Times in 355 Posts
+1^^^^^ There are chargers that charge ot 80%, 90% or 100% variably (just set as desired). Usually I charge to 80% unless I need more for a particular ride..
2old is offline  
Old 03-21-22, 05:34 PM
  #4  
newbert
Senior Member
Thread Starter
 
Join Date: Aug 2013
Posts: 55
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 11 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Originally Posted by 2old View Post
+1^^^^^ There are chargers that charge ot 80%, 90% or 100% variably (just set as desired). Usually I charge to 80% unless I need more for a particular ride..
Thanks for all the detailed info, mclewis1!

2old, Can you provide a link to any of these variable chargers? I've never heard of these .....Do they work with any e-bike battery?

Thanks!
newbert is offline  
Old 03-21-22, 07:35 PM
  #5  
fooferdoggie 
Senior Member
 
Join Date: Jan 2020
Posts: 1,563
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 429 Post(s)
Liked 545 Times in 327 Posts
there are so many factors. but getting used to your bike and how much battery you use helps. I have a bosch system and don't worry about it their batteries last about the longes of any bike and who knows maybe it doesn't to change fully? their BMS is pretty elaborate. plus I often use most of the battery every day.
fooferdoggie is offline  
Old 03-21-22, 08:43 PM
  #6  
mclewis1
Member
 
Join Date: Dec 2020
Posts: 42
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 8 Post(s)
Liked 28 Times in 20 Posts
The Luna Advanced 300w charger https://lunacycle.com/batteries/chargers/ is one of the more popular battery chargers with variable capacities and amperage. I have a commercial 52v battery from Grin and instead of their fixed amperage model charger (or the wonderful but expensive Satiator) I went with the Luna Advanced model. I had to fabricate a small adapter pigtail (ST-3 charge port to XT60 connector) but otherwise I use it as is. It has settings for 80, 90, or 100% charge points at 1 to 5 amps ... but the most valuable feature (IMHO) is the voltage/amperage display. I generally charge my battery when it gets well under 50% and bring it up to 80% at 2 amps. If I need more capacity (those wonderful Sunday rides) I'll top it up to 100% and if time is limited I'll do it at 4 or 5 amps (my battery is rated to be charged at up to 8 amps).
mclewis1 is offline  
Likes For mclewis1:
Old 03-22-22, 07:39 AM
  #7  
2old
Senior Member
 
Join Date: Jul 2014
Location: socal
Posts: 3,422
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 678 Post(s)
Liked 466 Times in 355 Posts
newbert, mc provided the news and my charger is the Luna one too. As stated, you may need to fabricate a connector for the XT-60 on the Luna to your battery. For me, not necessary since both of my DIY batteries have those connectors.
2old is offline  
Old 03-27-22, 05:54 PM
  #8  
Calsun
Senior Member
 
Join Date: Mar 2021
Posts: 478
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 192 Post(s)
Liked 104 Times in 83 Posts
Batteries are rated for a set number of charge cycles. If you recharge at 70% instead of at 35% you can expect half the life with the battery. I recommend using the bike and checking the amount of discharge after each ride. This will provide a good idea of how much the battery charge level has been depleted to cover a certain distance.

My bike has eco, sport, and turbo modes and I set the eco mode for the percentage motor contribution I want and use it 100% of the time to maximize the miles per battery charge. On hills I drop into a lower gear rather than use a higher power mode. I get more exercise and the battery should last longer with fewer recharges needed.
Calsun is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.