battery charger for 15 amp battery,
- Thread starter 40Hotrod
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tomjasz
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Batteries are not typically rated by the amp. Ah, Amp-hours and voltage. What is the voltage of your battery? What is the manufacturer's maximum charge A, Amperage?
6zfshdb
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It is critical that there is compatibility between the charger and the battery BMS. Some battery / charger combinations have more that just +/- leads. As @tomjasz asks above, more details are necessary to answer your question. Who makes the battery and how many pins are there on the charge connector?
In general, higher currents cause more heat which is the enemy of any battery. 4 amps however isn't excessive and should be doable depending on manufacturer recommendations.
If cost isn't an issue, there are several quality chargers out there, including those from Grin and Luna, that are programmable for different voltages and current settings. Getting the proper connectors can sometimes be an issue though.
In general, higher currents cause more heat which is the enemy of any battery. 4 amps however isn't excessive and should be doable depending on manufacturer recommendations.
If cost isn't an issue, there are several quality chargers out there, including those from Grin and Luna, that are programmable for different voltages and current settings. Getting the proper connectors can sometimes be an issue though.
6zfshdb
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You may be able to find a relatively inexpensive 4 amp 48V charger but finding one with the correct connector & polarity could be an issue.
Can you post a picture of the battery and/or charger connector to help with identification?
BTW, some manufacturers rate their batteries at 48V when in reality, they are actually 52V. You need to measure the fully charged battery voltage to be sure. If it measures 58.8 V, it's a 52V battery and you need a 52V charger.
Can you post a picture of the battery and/or charger connector to help with identification?
BTW, some manufacturers rate their batteries at 48V when in reality, they are actually 52V. You need to measure the fully charged battery voltage to be sure. If it measures 58.8 V, it's a 52V battery and you need a 52V charger.
m@Robertson
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OK so that tells us your battery needs to have a charger that maxes out at 54.6v. It would also need to have a matching plug to your existing battery, and therein lies the rub, most likely. Its not like you can't find a matching plug - the use of a 2.5mm barrel adapter is common - but the issue comes from the amperage you want to pump thru it. Barrel adapters are at their maximum safe level of transmission - depending on who you ask - at 3 to 3.5 amps. 4 amps is over the safe limit.
Now, aftermarket or custom batteries typically have XT60 charge adapters and those are good for many more amps. But commercial products, not so much. You will want to know the plug and its limits before you move on to the next step, which is determining whether your battery's BMS will tolerate the higher current level or whether it will refuse same.
Really... lower charge amps are a lot better for your battery. A 15ah pack is not all that large. 4a is probably fine. Probably. 3a is still a 50% increase in your current rate of charge. I'd stop there. The 185w model described here will be rock-solid forever. And you can dial down the amperage if you have more time to spare (as well as do 80% charges).
An Ultra Reliable Ebike Battery Charger…
How about a charger – quickly adjustable for voltage and current – that is rated for hundreds of thousands of hours of use before it typically fails?
talesontwowheels.com
tomjasz
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I’ve made a few adapters for members. IF I have their connectors. I do have a fair selection. I just ask members to cover the shipping. It’s a shame to have mine end up in recycling. I stopped selling them when a couple of asshats fleeced me with fraudulent PayPal claims. That said, I’m slow…
tomjasz
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You have this. And most are not good over 2-3amp charging.
This from Grin, but I’d not go over 3. I agree with m@!
The DC barrel connector has been a standard for powering electronic devices with low voltage DC in consumer electronics, and has found its way as a commonly used plug for the charging port of frame mounted ebike batteries. We have also been using it for many years as the DC power port on the Cycle Analyst for running ebike lights, DC-DC converters, and other accessories.
These DC jack plugs are not usually rated for very high currents, and their design makes it easy to accidentally short the pin and ground tabs with a piece of metal. There are some models that have a multi-prong ground connection and are rated for up to 7 amps, but most of the models are only good for 2-4 amps. This is especially true if the mating contact to the ground sheath is just a single bent metal tab.
The low current rating and vulnerability to shorts make them far from ideal for use as the charge port in an ebike battery pack, but for better or for worse this is a common connector that is in many battery enclosures. Be aware that polarity can vary from device to device and DC plugs are specified by both the diameter of the barrel (OD) and pin (ID). The standard size used in ebikes has a 5.5mm barrel, but the pin can be either 2.5mm (most common) or a smaller 2.1mm (less common).
This from Grin, but I’d not go over 3. I agree with m@!
DC Jack
The DC barrel connector has been a standard for powering electronic devices with low voltage DC in consumer electronics, and has found its way as a commonly used plug for the charging port of frame mounted ebike batteries. We have also been using it for many years as the DC power port on the Cycle Analyst for running ebike lights, DC-DC converters, and other accessories.
These DC jack plugs are not usually rated for very high currents, and their design makes it easy to accidentally short the pin and ground tabs with a piece of metal. There are some models that have a multi-prong ground connection and are rated for up to 7 amps, but most of the models are only good for 2-4 amps. This is especially true if the mating contact to the ground sheath is just a single bent metal tab.
The low current rating and vulnerability to shorts make them far from ideal for use as the charge port in an ebike battery pack, but for better or for worse this is a common connector that is in many battery enclosures. Be aware that polarity can vary from device to device and DC plugs are specified by both the diameter of the barrel (OD) and pin (ID). The standard size used in ebikes has a 5.5mm barrel, but the pin can be either 2.5mm (most common) or a smaller 2.1mm (less common).
m@Robertson
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- USA
What he said 
Forget about 4a charging. Go three. Do that 185w unit described in the article above, put an xt60 plug on it and then on top of that one of these (I bought a couple myself and paid the 4.99 they ask for them):
![female_xt60_to_male_barrel_close_1024x1024[1].jpg](https://forums.electricbikereview.com/attachments/female_xt60_to_male_barrel_close_1024x1024-1-jpg.128258/ "female_xt60_to_male_barrel_close_1024x1024[1].jpg")
If you change your battery down the road or get a different bike, you just change adapter plugs.
Interesting that your charger says 54.4v. That tells me the manufacturer built in some safety fudge on their charger. Not a bad idea, but its an oddball value that you may find another one of, but its not common. With an adjustable charger you can dial that in. I'd go lower in fact. An 80% charge on a '48v' battery is 51.5v.
talesontwowheels.com
Forget about 4a charging. Go three. Do that 185w unit described in the article above, put an xt60 plug on it and then on top of that one of these (I bought a couple myself and paid the 4.99 they ask for them):If you change your battery down the road or get a different bike, you just change adapter plugs.
Interesting that your charger says 54.4v. That tells me the manufacturer built in some safety fudge on their charger. Not a bad idea, but its an oddball value that you may find another one of, but its not common. With an adjustable charger you can dial that in. I'd go lower in fact. An 80% charge on a '48v' battery is 51.5v.
Li-Ion Ebike Battery Charge Charts
Whats an 80% charge on a 48v battery? These charts give answers to questions like this on common ebike battery voltages: 36v, 48v, 52v, 60v and 72v.
talesontwowheels.com
tomjasz
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