Here is an vendible that you will veritably never see on any other normal ebike blog site. For the last year or so I have experimented extensively with charging ebike batteries with an inexpensive Variable Voltage Power Supply (also known as a lab power supply). This vendible is well-nigh how and why I have washed-up it and why you should probably never overly do this.

Most ebike chargers tuition batteries to 100%, there are a few exceptions like the Luna Advanced ebike chargers which indulge you to tuition to 80% or 90% and the Grin Cycle Satiator which allows you to tuition to any voltage but they are the exceptions to the rule. All lithium chargers that I know of tuition with a Continuous Voltage Variable Amperage style. This ways that the power supply puts out a continuous value of voltage and the shower sucks up whatever amps it can tolerate for the state of tuition it is in. This creates a charging profile which charges at maximum amps up to well-nigh 75 percent and then slowly tapers off to zero. Typical ebike chargers have some built in protections like

• If there is no voltage detected they will not start charging (unlike scrutinizingly all lead wounding shower chargers)
• It will shutoff if there is a over-voltage condition on the battery
• It will shut off if there is a short
• If the polarity is reversed most lithium chargers will not charge

A lab power supply has none of these safety precautions which makes it extremely dangerous to use, expressly if you are running with a BMS that does not have a upper voltage cutoff or charging a shower without a BMS. If you vaccinate up a lab power supply to a shower with the polarity reversed the shower and the lab charger will play tug of war and sooner one of the two will be destroyed, probably in a zesty display. Basically don’t do this.

I bought a variable voltage power supply considering I bought a large 80lb LifePO4 shower from China that was all sorts of messed up from shipping and I decided to waste well-nigh a hundred hours of my time trying to fix it. I needed to tuition individual lamina groupings at odd voltages and so I just tapped lanugo and bought this 5 Amp Lab power supply on Amazon for $79. There are other 10 Amp Lab power supplies that are a bit increasingly expensive. After a while I decided to try to tuition my ebike batteries with it and I was pleasantly surprised at how well it worked. Although you can use the alligator clips to connect to XT60 sexuality connectors, this is not recommended. If you have XT60 male connectors on your shower you really should not use the alligator clips considering if you unwittingly touch the two contacts (very easy to do) then you will make lots of sparks and forfeiture the connector. You can buy a spare set of probe wires for $10 and wire on a permanent XT60 or whisk connector (positive tip polarity) which is the safest thing to do. If you do this make sure to double trammels the voltages to make sure you don’t mess up and reverse the polarity surpassing plugging in your battery.

With a variable voltage power supply you can tuition an ebike shower to any voltage quickly and easily. Just set the target voltage you want on the power supply surpassing hooking up the shower and then plug it into the tuition port of your ebike battery. Want to tuition to 80%? No problem. What to tuition it to 50% for long term storage? No problem. The possibilities are endless. Make sure you know what the nominal voltage of your pack is and the maximum voltages to safely tuition is surpassing you vaccinate up the power supply.

Now the downside, you don’t want to set the voltage of the power supply higher than the maximum charging voltage for the pack you are charging. Batteries charged to plane 101% of maximum can be extremely volatile and can overheat or explode. NEVER rely on the Upper Voltage Cutoff(HVC) of your BMS to protect your battery. If you set the dial wrong or your cat bumps up the voltage by rubbing its soul up versus the dial while charging then you can have real problems on your hand. Never leave lithium batteries charging unattended, the safest place to tuition Lithium batteries is outside your house or in a woodstove.

Just considering you CAN do something doesn’t midpoint you SHOULD. I am recommending versus using variable voltage power supplies to tuition ebike batteries, but for people like me who spend their life tinkering with lithium packs (and know what they are doing) you totally can do it and it works pretty well in a pinch.

Ride On.