Batteries read full but arent ??

[lillady]

I recently got an ebike and drove and charged it numerous times before I noticed the charger was a lithium charger and my bike batteries are lead acid .the other day the battery was full but it went dead two blocks away so I bought a 60v battery charger for lead acid .when I hooked up the charger it read batterys were full(green light)the barryies all say 12. Something when I tested with multimeter and .1 amps what else can I check or why are the batteries not charging ?

 

[E-HP]

so I bought a 60v battery charger for lead acid .when I hooked up the charger it read batterys were full(green light)the barryies all say 12.

You didn’t say what voltage the pack is. When you say you got a 60v charger, does that mean it outputs 60v or is designed for a 60v lead acid battery? If you have a 60v lead acid battery, then it would be 72v fully charged (so 12v per battery would be very low.

 

[lillady]

Thank you for replying E-HP
Sorry your right .. I have 5 12v batteries making up a 60v pack I guess, wired in series.The charger info reads as follows Input Voltage : 110VAC 50/60Hz . Output: DC 68V-74 V , Power:240W . Charging current: 3 A max. Now I just notice tonight that the dc/dc converter has 4 wires but the one with the black and red wire together has been cut off (this is a previously owned bike )

 

[fill]

Dry cells?
Are the batteries sealed or not and have you checked and topped up the electrolyte with distilled/pure water if unsealed ?

 

[lillady]

They were dry yes so I cleaned out sulfate with baking soda and water , as much as possible ,and topped up with distilled water and epson salts.After which I tested each 12vbattery and all the readings except one (which I redid the process on again) was in the 12-13 range.hooked the new charge and still get only a green light .I'm beginning to get discouraged and confused about the green light on the charger not turning red.

 

[fill]

They were dry yes so I cleaned out sulfate with baking soda and water , as much as possible ,and topped up with distilled water and epson salts.After which I tested each 12vbattery and all the readings except one (which I redid the process on again) was in the 12-13 range.hooked the new charge and still get only a green light .I'm beginning to get discouraged and confused about the green light on the charger not turning red.

So you have replaced the dilute sulphuric acid (H2SO4) in your battery with magnesium sulphate solution MgSO4. yeah I think we have found the problem.. any local garage should be able to top up your batteries with acid, just drain them first and dont tell them what you did, well you can but i suspect they will laugh at you so...

edit actually rinse out the mgso4 too im not sure how that would react to acid and the rest of the battery chemistry?? if you have charged a lot you could have killed the battery? again the chemistry is beyond me..

 

[lillady]

So you have replaced the dilute sulphuric acid (H2SO4) in your battery with magnesium sulphate solution MgSO4. yeah I think we have found the problem.. any local garage should be able to top up your batteries with acid, just drain them first and dont tell them what you did, well you can but i suspect they will laugh at you so...

edit actually rinse out the mgso4 too im not sure how that would react to acid and the rest of the battery chemistry?? if you have charged a lot you could have killed the battery? again the chemistry is beyond me..

I'm a 61yr old woman what do I know .Just goes to show ...you cant always believe what you read on the internet!!
So I guess it's safe to assume the chargers ok it's the BMS doing whatits supposed to do ? But why do the reading all say over 12V

 

[fill]

I'm a 61yr old woman what do I know .Just goes to show ...you cant always believe what you read on the internet!!
So I guess it's safe to assume the chargers ok it's the BMS doing whatits supposed to do ? But why do the reading all say over 12V

hey, we all err on occasion. and you found out virtually not in person at the garage,,
I tried to be polite about it .. but almost didnt warn you about the garage staff laughing

as to why the batteries work at all? i can only guess that the initial rinse didnt neutralise/remove all the acidic components and charging had some chemical impact, test with indicator paper for ph distilled water is neutral ph7 as is mgso4 so if the electrolyte is acidic then thats why.. my understanding is basic a battery when charged is in one chemical state, as its discharged the chemistry changes towards a different state and recharging restores the original state..

what the magnesium sulphate is doing and how it reacts????? its been longer for me since i was in school so?

in your situation i would look for a real lead acid battery expert for advice, the mgso4 could well be benign but tbh i dont know? try a new thread with a topic like "lead acid battery help needed" to get the right attention

 

[Danhunt56]

I'm a 61yr old woman what do I know .Just goes to show ...you cant always believe what you read on the internet!!
So I guess it's safe to assume the chargers ok it's the BMS doing whatits supposed to do ? But why do the reading all say over 12V

I'm a 61yr old woman what do I know .Just goes to show ...you cant always believe what you read on the internet!!
So I guess it's safe to assume the chargers ok it's the BMS doing whatits supposed to do ? But why do the reading all say over 12V

12.6 volts for a 12 volt battery is fully charged. It will likely be higher right at the end of charging. I don’t think you have written what the voltage is with the batteries combined into a bank. Your charger is sensing that and seeing that voltage as charged. My chargers are free when they aren’t hooked up, so if something is wrong with the pack connection and your voltage is zero you might get a green light then as well.

You began by saying the bike stopped after a few blocks? If your bank of batteries are coming out to 60 plus volts it’s not the batteries. And the scooter likely anyways would run on lead acid way lower then you ever should discharge them because, as far as I know, only lithium batteries have battery management systems (bms), so there is nothing to stop it from discharging to zero, (if you every left a light on in your car and came back in a few weeks later you know what I mean). You need to follow your wires and test at every junction, or start at the motor and see if the voltage is getting to it. Then see if it is getting to the controller. Then work back to the battery checking for maybe a fuse or a switch along the way. Also, if you have any safety power cutoffs such as brakes, make sure those aren’t activated.

 

[lillady]

12.6 volts for a 12 volt battery is fully charged. It will likely be higher right at the end of charging. I don’t think you have written what the voltage is with the batteries combined into a bank. Your charger is sensing that and seeing that voltage as charged. My chargers are free when they aren’t hooked up, so if something is wrong with the pack connection and your voltage is zero you might get a green light then as well.

You began by saying the bike stopped after a few blocks? If your bank of batteries are coming out to 60 plus volts it’s not the batteries. And the scooter likely anyways would run on lead acid way lower then you ever should discharge them because, as far as I know, only lithium batteries have battery management systems (bms), so there is nothing to stop it from discharging to zero, (if you every left a light on in your car and came back in a few weeks later you know what I mean). You need to follow your wires and test at every junction, or start at the motor and see if the voltage is getting to it. Then see if it is getting to the controller. Then work back to the battery checking for maybe a fuse or a switch along the way. Also, if you have any safety power cutoffs such as brakes, make sure those aren’t activated.

 

[lillady]

Thank you danhunt56 that is the most detailed (in plain layman's terms) and helpful info I've gotten so far..that advice I can understand clearly.