Help! Battery Recharge Intervals

[georgehenry]

Hi Andy-Mat

I copy what I said above.

"My Yamaha 400Wh battery is entering its 6th year and is performing seemingly exactly as it did when new. It has covered 11,900 miles or 19,151km.

I use my bike to commute to work and back.

I store my battery indoors at about 65% charged and charge it back to full prior to my off road 12/14 mile ride to work. I charge it back to full while at work after having used 25% to 30% of its capacity. I ride it 10 miles home on the road using higher assist levels to average around 20mph for the 10 mile journey. I then store the battery in the house at the above mentioned 60%/65% charge level.

I only charge it back to full when I next use the bike. The time gap between charges could be only until the next day or as much as six weeks after bringing the battery into the house.

Used in this way my 400Wh Yamaha battery seems to be lasting extremely well."

So I charge my Yamaha battery from about 65% to full 100% as close to when I depart for work as I can. I do not use a timer plug with my Yamaha battery and Yamaha Charger and it would seem likely that the charger completely stops charging once it has completed charging and balancing the battery.

(I do have a Chinese derived rear hub electric bike with a generic Chinese charger probably similar to your own and also like you I use a timer plug with this charger that allows me to set a time limit for how long the charger is connected to the mains supply with 6 choices, 15min, 30min, 1hr, 2hrs, 4hrs and 8hrs.)

When I get to work I have generally used about 25% to 30% of the 400Wh Yamaha batteries capacity. Before I start work I plug my battery into the charger and switch it on to charge.

I will usually be away from the battery for between 6 and 9 hours while I am working. The battery will have become fully charged within a couple of hours. So my Yamaha battery and charger remain attached and switched on at the mains for probably between 4 and 7 hours before I can unplug it.

As my battery has worked so well, and for so long, I believe that the Yamaha system is well designed and the battery of high quality.

I use higher assistance levels to travel home on a 10 mile undulating B road route where I average 20mph and complete the journey in 30 minutes plus and occasionally minus a bit. My battery will normally have about 65% of its capacity remaining. I store my battery in the house and only charge it again as close to when I will be departing to ride to work as possible.

So as you can see I do a few things that you believe to be detrimental to the longevity of an electric bike battery and which judged by the continuing excellent performance of my Yamaha battery have not been detrimental to mine.

1. For the whole of my batteries life I have been only partially discharging the battery before charging it back to full.

2. My battery has spent a large proportion of its life connected to a switched on Yamaha charger after it has finished charging the battery to full.

However I think we both agree that it is not a good idea to leave these batteries fully charged too long before you use them.

If you have found no issues using your own battery until it is empty before re charging it, I might be wrong to worry too much about deeply discharging my battery.

I think we can both agree that it is certainly a good idea to look after these expensive batteries as well as possible.

 

[Andy-Mat]

Hi Andy-Mat

I copy what I said above.

"My Yamaha 400Wh battery is entering its 6th year and is performing seemingly exactly as it did when new. It has covered 11,900 miles or 19,151km.

I use my bike to commute to work and back.

I store my battery indoors at about 65% charged and charge it back to full prior to my off road 12/14 mile ride to work. I charge it back to full while at work after having used 25% to 30% of its capacity. I ride it 10 miles home on the road using higher assist levels to average around 20mph for the 10 mile journey. I then store the battery in the house at the above mentioned 60%/65% charge level.

I only charge it back to full when I next use the bike. The time gap between charges could be only until the next day or as much as six weeks after bringing the battery into the house.

Used in this way my 400Wh Yamaha battery seems to be lasting extremely well."

So I charge my Yamaha battery from about 65% to full 100% as close to when I depart for work as I can. I do not use a timer plug with my Yamaha battery and Yamaha Charger and it would seem likely that the charger completely stops charging once it has completed charging and balancing the battery.

(I do have a Chinese derived rear hub electric bike with a generic Chinese charger probably similar to your own and also like you I use a timer plug with this charger that allows me to set a time limit for how long the charger is connected to the mains supply with 6 choices, 15min, 30min, 1hr, 2hrs, 4hrs and 8hrs.)

When I get to work I have generally used about 25% to 30% of the 400Wh Yamaha batteries capacity. Before I start work I plug my battery into the charger and switch it on to charge.

I will usually be away from the battery for between 6 and 9 hours while I am working. The battery will have become fully charged within a couple of hours. So my Yamaha battery and charger remain attached and switched on at the mains for probably between 4 and 7 hours before I can unplug it.

As my battery has worked so well, and for so long, I believe that the Yamaha system is well designed and the battery of high quality.

I use higher assistance levels to travel home on a 10 mile undulating B road route where I average 20mph and complete the journey in 30 minutes plus and occasionally minus a bit. My battery will normally have about 65% of it capacity remaining. I store my battery in the house and only charge it again as close to when I will be departing to ride to work as possible.

So as you can see I do a few things that you believe to be detrimental to the longevity of an electric bike battery and which judged by the continuing excellent performance of my Yamaha battery have not been detrimental to mine.

1. For the whole of my batteries life I have been only partially discharging the battery before charging it back to full.

2. My battery has spent a large proportion of it life connected to a switched on Yamaha charger after it has finished charging the battery to full.

However I think we both agree that it is not a good idea to leave these batteries fully charged too long before you use them.

If you have found no issues using your own battery until it is empty before re charging it, I might be wrong to worry too much about deeply discharging my battery.

I think we can both agree that it is certainly a good idea to look after these expensive batteries as well as possible.

Good post.
Do you happen to know which cells are installed in the battery?
I am unsure as to whether Yamaha make their own cells, or buy in...
My batteries, 3 for my current bike (one on loan to use and keep active with), and the one for my previous bike were/are all Panasonic batteries, which I am really happy with.
I keep getting told here that other manufacturers are better, but never see any positive proof, but I know that Panasonic really do put their money where their mouth is!
Regards for a great Easter.
Andy

 

[sjpt]

So just to clarify, whether you recharge a battery from say 80% or from BMS cut off (as you said) does that then class as a full recharge i.e if say the battery is capable of 3000 recharges, would either situation be one less recharge off the total?

Bosch explicitly state A charge cycle refers to the full recharging of a battery in a single charging session or several partial charging sessions.

eBike batteries: Long range, low weight, easy charging

The high-quality, long-lasting eBike batteries from Bosch have the highest energy density with a small size and light weight. The Bosch PowerTube is fully integrated in the frame. Different capacities offer the right choice for replacement and spare batteries.

www.bosch-ebike.com

Of course, there may be people on this forum who say that because Bosch state it, it must be wrong. They may even go so far as to say that Bosch say it in order to increase sales of their (inflated price) batteries.

 

[Amoto65]

Of course, there may be people on this forum who say that because Bosch state it, it must be wrong. They may even go so far as to say that Bosch say it in order to increase sales of their (inflated price) batteries.

These same people may also say the world is flat and 5g masts are the cause of the pandemic....

 

[Andy-Mat]

Good post.
Do you happen to know which cells are installed in the battery?
I am unsure as to whether Yamaha make their own cells, or buy in...
My batteries, 3 for my current bike (one on loan to use and keep active with), and the one for my previous bike were/are all Panasonic batteries, which I am really happy with.
I keep getting told here that other manufacturers are better, but never see any positive proof, but I know that Panasonic really do put their money where their mouth is!
Regards for a great Easter.
Andy

I should have said Panasonic "CELLS"! My bad...
Andy

 

[Andy-Mat]

Bosch explicitly state A charge cycle refers to the full recharging of a battery in a single charging session or several partial charging sessions.

eBike batteries: Long range, low weight, easy charging

The high-quality, long-lasting eBike batteries from Bosch have the highest energy density with a small size and light weight. The Bosch PowerTube is fully integrated in the frame. Different capacities offer the right choice for replacement and spare batteries.

www.bosch-ebike.com

Of course, there may be people on this forum who say that because Bosch state it, it must be wrong. They may even go so far as to say that Bosch say it in order to increase sales of their (inflated price) batteries.

You have a very good point in your comments, that I do not disagree with!!
Andy

 

[Andy-Mat]

These same people may also say the world is flat and 5g masts are the cause of the pandemic....

Very unlikely....Those sort of people don't understand anything to do with electricity either, but they are around everywhere!
Andy

 

[PJK]

Hi guys, I have a Li-on lithium battery for my Cyclamatic e-bike that seems to be playing up. I need some advise but, as I’m new to this forum, not sure if this is the correct thread to post my query on. Would it be OK to discuss here?

 

[Fishy]

Hi guys, I have a Li-on lithium battery for my Cyclamatic e-bike that seems to be playing up. I need some advise but, as I’m new to this forum, not sure if this is the correct thread to post my query on. Would it be OK to discuss here?

Hi, and welcome. Probably best to start a new thread, you'll likely get more response.

 

[Essgeebee]

Can someone please clarify best practice for battery recharge. I have Bosch a 400Wh Battery and over winter when not in use I kept it indoors at about 60% charge. Recently I've been doing short daily rides only burning about 15%. Should I always top it back up to 100% before next day or let it go down lower before recharge to 100%. Thanks.

I lifted these from my Kalkhoff Pro Connect's user manual. It is six years old and uses a Li-ion battery. Unless battery technology has changed dramatically, I expect the principles apply to other ebike Li-ion batteries.

• You can extend the service life of the battery by fully recharging it after every journey, however short. The Xion Li-ion battery has no memory effect.
• If you continuously run the battery to empty during normal operation, this reduces its service life. Frequent partial recharging of the battery has a favourable effect on its service life. You should therefore partially recharge the battery whenever possible: Do not run the battery all the way down to empty and recharge it even after a short period of operation.
• If you do not need your battery for a while, store it at a temperature of +10°C at 50-70% of its full charge capac- ity. If you do not use the battery for six months, you must recharge it.
  
  
  
  

 

[sjpt]

• If you do not need your battery for a while, store it at a temperature of +10°C at 50-70% of its full charge capacity.

I agree with your points and what that says. There seems to be some discussions about what 'for a while' might mean. Some people suggest a week or so, some more like a month or more, some quite a bit less. We tend to charge ours up fairly frequently and are not typically sure in advance when/how much we might want it (*); so after charge it often stays on 100% for three or four days. Others say its better to charge to 80%, then the last 20% just before you need it.

(*) It for us is actually two batteries, one for the tandem and one for the solo we share. We are uncertain about when we will want to use which.

 

[Essgeebee]

FWIW until recently I hadn’t used my Kalkhoff for over two years due to illness and lethargy. It, and its two batteries, sat in my in unheated garage throughout that time, never touched. They were almost at full charge when I stored them in 2018 and when I first took my bike out a few weeks ago, both batteries showed almost fully charged still. I really did expect them to fail or play up in some way to repay my neglect but having done trips totalling about 80 miles, swapping batts several times and recharging them after each ride, they’ve performed flawlessly (touch wood).
I’ve concluded that good quality batteries are tolerant of less than perfect management, though I intend to take better care of them now I am back in the saddle.