Do I need a new battery soon?

[John F]

I have a Woosh Santana CD which is 37 months old. The 15 amp battery is marked "PICC The Top Energy System" It's been charged 240 times. The battery has a 3 led indicator on the rear (x 2) One light shows red, one green and the 3rd is unlit)

After an 18 mile ride today, the King Meter battery indicator is down by one. From memory, from some of my earlier longer rides, it doesn't take too long for it then to go flat. So I'm guessing that the battery may have lost half its capacity and its range decreased to say 25miles? Is this "par for the course"?

I read recently that the cost of lithium batteries has fallen by a half in the last 3 years. I was hoping that my battery (original replacement cost £300) would have come down in price to reflect this. Sadly it's gone up to £345! So what's going on here?!

Woosh have told me that batteries have improved in that they now can put a greater number of cells in. What would be the benefit to the user of this increase? (A new battery would not necessarily be the same make)

They may be able to offer a refurbished battery. Is this a good option?

Can anyone offer advice on what to do?

 

[trex]

After 240 charges, I reckon the battery has lost about 15% of its initial capacity. When the battery ages, the voltage sag becomes more apparent, ie the bike loses its oomph more quickly. You only have to increase the assist level to compensate. It may still have another 18 months left.

 

[Deleted member 4366]

You only need to replace a battery when it no longer gives you the range that you need. When it comes to replacement, you don't have to fit the same one. You can use any 36v battery that you can find on Ebay or Aliexpress as long as you can figure out a way to fix it to your bike. You should be able to get a good battery for about £200.

Your motor controller sits in a compartment at the front of your battery. If you want to fit a different type of battery, you can put the controller in a saddle bag like what I've done on my bike.



Here's a regular no name rack battery fitted to a normal bike rack:



Same again on a Raleigh Shopper:

 

[anotherkiwi]

I don't trust the LCD battery meter. Some LCDs have a "smart" mode where it tries to guess how much you have left. Like people machines are not very good at guessing some times...

If you can wire a Watt meter between the battery and the controller it will give much better indication of the health of your battery.

 

[Fordulike]

I have a Woosh Santana CD which is 37 months old. The 15 amp battery is marked "PICC The Top Energy System" It's been charged 240 times. The battery has a 3 led indicator on the rear (x 2) One light shows red, one green and the 3rd is unlit)

After an 18 mile ride today, the King Meter battery indicator is down by one. From memory, from some of my earlier longer rides, it doesn't take too long for it then to go flat. So I'm guessing that the battery may have lost half its capacity and its range decreased to say 25miles? Is this "par for the course"?

I read recently that the cost of lithium batteries has fallen by a half in the last 3 years. I was hoping that my battery (original replacement cost £300) would have come down in price to reflect this. Sadly it's gone up to £345! So what's going on here?!

Woosh have told me that batteries have improved in that they now can put a greater number of cells in. What would be the benefit to the user of this increase? (A new battery would not necessarily be the same make)

They may be able to offer a refurbished battery. Is this a good option?

Can anyone offer advice on what to do?

If I were getting 18 miles plus out of a 3 year old battery of that capacity and charge cycles, then I would still be happy.

As d8ve says, only replace if you are not happy with the range.

 

[IR772]

I don't trust the LCD battery meter. Some LCDs have a "smart" mode where it tries to guess how much you have left. Like people machines are not very good at guessing some times...

If you can wire a Watt meter between the battery and the controller it will give much better indication of the health of your battery.

?

 

[John F]

I don't trust the LCD battery meter. Some LCDs have a "smart" mode where it tries to guess how much you have left. Like people machines are not very good at guessing some times...

If you can wire a Watt meter between the battery and the controller it will give much better indication of the health of your battery.

I just have a multi meter. The voltage at the 18 mile partialy discharged point was 37.9. After charging it was 41.8 if this helps.

 

[John F]

You only need to replace a battery when it no longer gives you the range that you need. When it comes to replacement, you don't have to fit the same one. You can use any 36v battery that you can find on Ebay or Aliexpress as long as you can figure out a way to fix it to your bike. You should be able to get a good battery for about £200.

Your motor controller sits in a compartment at the front of your battery. If you want to fit a different type of battery, you can put the controller in a saddle bag like what I've done on my bike.



Here's a regular no name rack battery fitted to a normal bike rack:



Same again on a Raleigh Shopper:

You only need to replace a battery when it no longer gives you the range that you need. When it comes to replacement, you don't have to fit the same one. You can use any 36v battery that you can find on Ebay or Aliexpress as long as you can figure out a way to fix it to your bike. You should be able to get a good battery for about £200.

Your motor controller sits in a compartment at the front of your battery. If you want to fit a different type of battery, you can put the controller in a saddle bag like what I've done on my bike.



Here's a regular no name rack battery fitted to a normal bike rack:



Same again on a Raleigh Shopper:

Had a look at Aliexpress, and its all a bit confusing. Presumably I could use my existing metal case and find one the right size to fit?

 

[John F]

You only need to replace a battery when it no longer gives you the range that you need. When it comes to replacement, you don't have to fit the same one. You can use any 36v battery that you can find on Ebay or Aliexpress as long as you can figure out a way to fix it to your bike. You should be able to get a good battery for about £200.

Your motor controller sits in a compartment at the front of your battery. If you want to fit a different type of battery, you can put the controller in a saddle bag like what I've done on my bike.



Here's a regular no name rack battery fitted to a normal bike rack:



Same again on a Raleigh Shopper:

What exactly is a "refurbished battery" ? Is it a sensible cost saving option?

 

[Nealh]

At 37.9v you may still have 10 miles left I reckon, LVC should be set for 33/34v. 41.8v is a well balanced pack so it sounds like it is still in good condition, though the rated capacity/ah may not all be there. Try riding it locally until the LVC cuts in then you will know exactly how many miles it is still good for.

 

[John F]

At 37.9v you may still have 10 miles left I reckon, LVC should be set for 33/34v. 41.8v is a well balanced pack so it sounds like it is still in good condition, though the rated capacity/ah may not all be there. Try riding it locally until the LVC cuts in then you will know exactly how many miles it is still good for.

Thanks. What's LVC?

 

[anotherkiwi]

Low Voltage Cutoff

 

[anotherkiwi]

I just have a multi meter. The voltage at the 18 mile partialy discharged point was 37.9. After charging it was 41.8 if this helps.

That is a very healthy battery, you aren't near half way through, most of the energy in a 36 V battery is at 36 V. My 10.4 Amp bottle battery only charges to 41.5 after just over a year. The hills around here are very hard on it. I can still eek about 60 km (37 miles) from it.

 

[Nealh]

Thanks. What's LVC?

Once you hit the LVC the batteries BMS ( Battery Management System incorporated on a PCB) will cut power to the controller and a error code will flash on your lcd. The LVC is a safety feature to prevent the battery from discharging to low rendering the cells useless.

 

[awol]

Once you hit the LVC the batteries BMS ( Battery Management System incorporated on a PCB) will cut power to the controller and a error code will flash on your lcd. The LVC is a safety feature to prevent the battery from discharging to low rendering the cells useless.

What volts should the batteries BMS cut it off at on a 36v battery?

 

[Nealh]

All of mine are about 33.5v (Li-on). Some batts are listed as 28v which is low and by then batteries will be well spent however most will not get that low as the controller also has a LVC, most Chinese 36v ones are at about 30/31v. Lipo 10s (37v) unprotected minimum I go is 3.5v to prevent them from wandering.