The Club Dash Logger is a fully configurable backlit display, controller and logging device. It offers the same quality and advanced technology as our top of the line. Subscribe and SAVE, give a gift subscription or get help with an existing subscription by clicking the links below each cover image. Table 2: Typical charge characteristics of lithium-ion. Adding full saturation at the set voltage boosts the capacity by about 10 percent but adds stress due to high. Ah, man, you see that up there? The Volkwsagen autonomous concept caterpillar called Sedric? Imaging hitting the road in this adorable little guy someday. The Future.

Charging Lithium- Ion Batteries – Battery University. Find out how to prolong battery life by using correct charge methods.

Charging and discharging batteries is a chemical reaction, but Li- ion is claimed to be the exception. Battery scientists talk about energies flowing in and out of the battery as part of ion movement between anode and cathode. This claim carries merits but if the scientists were totally right, then the battery would live forever. They blame capacity fade on ions getting trapped, but as with all battery systems, internal corrosion and other degenerative effects also known as parasitic reactions on the electrolyte and electrodes till play a role.

Chelios faces a Chinese mobster who has stolen his nearly indestructible heart and replaced it with a battery-powered ticker that requires regular jolts of. “The redeployment of tactical nuclear weapons is an alternative worth a full review,” Song added, though according to the Post did not mention Mattis’ response.

See BU- 8. 08b: What causes Li- ion to die?)The Li ion charger is a voltage- limiting device that has similarities to the lead acid system. The differences with Li- ion lie in a higher voltage per cell, tighter voltage tolerances and the absence of trickle or float charge at full charge. While lead acid offers some flexibility in terms of voltage cut off, manufacturers of Li- ion cells are very strict on the correct setting because Li- ion cannot accept overcharge. The so- called miracle charger that promises to prolong battery life and gain extra capacity with pulses and other gimmicks does not exist. Li- ion is a “clean” system and only takes what it can absorb. Charging Cobalt- blended Li- ion.

Li- ion with the traditional cathode materials of cobalt, nickel, manganese and aluminum typically charge to 4. V/cell. The tolerance is +/–5. V/cell. Some nickel- based varieties charge to 4. V/cell; high capacity Li- ion may go to 4. V/cell and higher.

Boosting the voltage increases capacity, but going beyond specification stresses the battery and compromises safety. Protection circuits built into the pack do not allow exceeding the set voltage. Figure 1 shows the voltage and current signature as lithium- ion passes through the stages for constant current and topping charge. Full charge is reached when the current decreases to between 3 and 5 percent of the Ah rating. Figure 1: Charge stages of lithium- ion. Li- ion is fully charged when the current drops to a set level. In lieu of trickle charge, some chargers apply a topping charge when the voltage drops.

Courtesy of Cadex. The advised charge rate of an Energy Cell is between 0. C and 1. C; the complete charge time is about 2–3 hours. Manufacturers of these cells recommend charging at 0. C or less to prolong battery life; however, most Power Cells can take a higher charge C- rate with little stress. Charge efficiency is about 9.

Some Li- ion packs may experience a temperature rise of about 5ºC (9ºF) when reaching full charge. This could be due to the protection circuit and/or elevated internal resistance.

Discontinue using the battery or charger if the temperature rises more than 1. C (1. 8ºF) under moderate charging speeds. Full charge occurs when the battery reaches the voltage threshold and the current drops to 3 percent of the rated current.

A battery is also considered fully charged if the current levels off and cannot go down further. Elevated self- discharge might be the cause of this condition.

Increasing the charge current does not hasten the full- charge state by much. Although the battery reaches the voltage peak quicker, the saturation charge will take longer accordingly. Seed Of Chucky Full Movie Online Free here. With higher current, Stage 1 is shorter but the saturation during Stage 2 will take longer.

A high current charge will, however, quickly fill the battery to about 7. Li- ion does not need to be fully charged as is the case with lead acid, nor is it desirable to do so. In fact, it is better not to fully charge because a high voltage stresses the battery. Choosing a lower voltage threshold or eliminating the saturation charge altogether, prolongs battery life but this reduces the runtime. Chargers for consumer products go for maximum capacity and cannot be adjusted; extended service life is perceived less important.

Some lower- cost consumer chargers may use the simplified “charge- and- run” method that charges a lithium- ion battery in one hour or less without going to the Stage 2 saturation charge. Ready” appears when the battery reaches the voltage threshold at Stage 1.

State- of- charge (So. C) at this point is about 8. Certain industrial chargers set the charge voltage threshold lower on purpose to prolong battery life. Table 2 illustrates the estimated capacities when charged to different voltage thresholds with and without saturation charge.

See also BU- 8. 08: How to Prolong Lithium- based Batteries.)Charge V/cell. Capacity atcut- off voltage Charge time. Capacity with full saturation.

Table 2: Typical charge characteristics of lithium- ion. Adding full saturation at the set voltage boosts the capacity by about 1. When the battery is first put on charge, the voltage shoots up quickly. This behavior can be compared to lifting a weight with a rubber band, causing a lag.

The capacity will eventually catch up when the battery is almost fully charged (Figure 3). This charge characteristic is typical of all batteries. The higher the charge current is, the larger the rubber- band effect will be. Cold temperatures or charging a cell with high internal resistance amplifies the effect. Figure 3: Volts/capacity vs.

The capacity trails the charge voltage like lifting a heavy weight with a rubber band. Courtesy of Cadex. Estimating So. C by reading the voltage of a charging battery is impractical; measuring the open circuit voltage (OCV) after the battery has rested for a few hours is a better indicator. As with all batteries, temperature affects the OCV, so does the active material of Li- ion. So. C of smartphones, laptops and other devices is estimated by coulomb counting. See BU- 9. 03: How to Measure State- of- charge.)Li- ion cannot absorb overcharge.

When fully charged, the charge current must be cut off. A continuous trickle charge would cause plating of metallic lithium and compromise safety. To minimize stress, keep the lithium- ion battery at the peak cut- off as short as possible. Once the charge is terminated, the battery voltage begins to drop. This eases the voltage stress. Over time, the open circuit voltage will settle to between 3.

V and 3. 9. 0V/cell. Note that a Li- ion battery that has received a fully saturated charge will keep the voltage elevated for a longer than one that has not received a saturation charge. When lithium- ion batteries must be left in the charger for operational readiness, some chargers apply a brief topping charge to compensate for the small self- discharge the battery and its protective circuit consume. The charger may kick in when the open circuit voltage drops to 4. V/cell and turn off again at 4. V/cell. Chargers made for operational readiness, or standby mode, often let the battery voltage drop to 4.

V/cell and recharge to only 4. V/cell instead of the full 4. V/cell. This reduces voltage- related stress and prolongs battery life. Some portable devices sit in a charge cradle in the ON position. The current drawn through the device is called the parasitic load and can distort the charge cycle. Battery manufacturers advise against parasitic loads while charging because they induce mini- cycles.

This cannot always be avoided and a laptop connected to the AC main is such a case. The battery might be charged to 4. V/cell and then discharged by the device. The stress level on the battery is high because the cycles occur at the high- voltage threshold, often also at elevated temperature.

High Speed electric motors High Torque electric motors. To start: Electric motors- AC vs.

DCI'll just put this plainly- you can't use an AC motor in a go- kart. Sure, it would be technically possible, and some electric cars use AC motors, but those are with $1. The reason is that AC is different from AC. AC stands for 'Alternating Current" and is what comes out of your wall socket.

It's used because it transmits long distances better along wires (from the power plant to you) and doesn't electrocute people quite so badly. DC stands for 'Direct Current' and is what comes out of a battery. It's plain electricity, and it's what you want to use for a go kart. To get more technical, AC is called 'alternating' because the polarity (the + and - ) reverses- in the AC in your house, it happens 6. An AC motor needs this. Now, it is possible to make AC out of DC.

Most people have seen inverters, which you can plug into you car's cigarette lighter and then plug in a laptop, blender, whatever. Why not just use one of those? The answer is current, and power. For a good electric go- kart, your power demands are going to be around 1. Because of surge current. An electric motor is an 'inductive' load. Have you ever seen your kitchen lights dim when the refrigerator or microwave comes on?

That's because those are both inductive loads, and inductive loads require a TON of power to start. Say some electric motor might need 2. Your 1. 00. 0 watts kart motor starting under load might need 5. Go price a 5. 00. Yeah, you don't want to do that. You might think that maybe you can make it work even though some people say it's a bad idea- trust me, I'm one of those people who chases down bad ideas to see what will happen. Don't even bother. So to be clear, you can't reasonably use any AC motor in a kart unless you want to go no further than your longest extension cord.

That means don't bother with any motor marked AC or which comes out of a washing machine, belt sander, or anything that plugs in to the wall. There are two exceptions to this: treadmills and really loud power tools.

Most treadmills use a 9. DC motor- the treadmill contains a rectifier which converts the AC to DC. Loud power tools like angle grinders and circular saws use a motor called a 'universal motors' which can operate on either AC or DC. I wouldn't use either a treadmill or universal motor either. Why not? They are made for 9. US) and not very powerful. While a treadmill motor might seem like it's powerful, consider that you're going to have to carry around at least seven batteries (of car battery size) to get enough voltage and power. It's the same as with the inverter- technically possible, but as a DIY go- kart maker, it's not what you want. OK, that's all bad news. What's the good news? Well, there are plenty of DC electric go cart motors out there perfect for go- karts.

What should you look for in a DC electric go cart motors? Low voltage. The lower the voltage, the fewer batteries you have to carry around. Also, if the rated voltage is lower, you can overvolt the motor, which gives you more power. Say you get a 2. 4v motor- you could run it on 3. Could you run it on 4. Yes.. but for a very short time.

Why? Well, putting that extra voltage in a electric go cart motor causes extra current to flow, which is where your power comes from. This is a problem because the more current that flows, the hotter the motor gets- and when it gets too hot, it will burn up, explode, and leave you standed. What happens is that the insulation in the electric go cart motor is rated for a certain lifetime (say 2.

If you double that temperature, that rating may drop to say, 1 year. If you get it really, really hot, it might fry in ten seconds. Don't overheat your motors. You could do a 1. You could do a 2.

You could do a 3. I wouldn't put more than 4. DC. A person with dry fingers can touch both terminals of a 1. However, do it with 1.

That's because it takes a certain amount of voltage to overcome your body (especially your skin) resistance. Once there's enough voltage to overcome that resistance, you're being electrocuted. It only takes 0. 0. If you're going to make an electric go kart, you need to educate yourself on electricity safety. I won't write that book here, but go read up on it- and don't put more than 4. Note: I'm not saying 4. Okay, safety lecture over. Where can you find good motors for electric go karts? D& D Motor Systems, Inc!!

The last thing I'll talk about with electric motors is their power ratings. There are two important things you need to know- electric motors are rated for continous power, meaning they can make that power all day, all night, for years on end. Gas engines are rated on instantaneous power, which is how much than can produce for a moment. Secondly, electric motors produce maximum torque (the force with which it spins the wheels) at zero RPM.

Have you ever ridden a two- stroke dirtbike? All the power comes around 5.

THEN you get power. Electric motors are the opposite- you get all your acceration at the very start, and it tapers off linearly as you speed up. This makes for very fun take- offs if your batteries, controller, and motor are up to it. What this means is that you have to think about electric power ratings differently. A Harbor Freight 6. HP gas motor might be fun, but a 6. HP electric motor is nearly 5. W = 1. HP) and will rip your face off and melt your batteries.

Sweet. You can use much smaller HP rated electric motor than you would a gas motor, and have the same amount of fun. So, how do you throttle an electric motor? You have three options: on/off control (likely to fry something), progressive on/off control with multiple batteries, and a controller. On/off control is where you just have a big switch (or more likely, a big relay or contactor) and you get full power as soon as your throw the switch. I wouldn't recommend this, as the surge power phenomenon which I mention above means that you're switching on a LARGE amount of current all at once, and quite frequently what this will do is actually weld the contacts of your switch in the closed position, which now means that you're sitting on a kart which is at full throttle and won't turn off.

I know a person who tried something like this on an electric motorcycle and has the scars to prove it. Unless it's small motor and big big switch, I'd avoid this. How about progressive on/off control? Simply, this means that you are switching on your batteries one at a time. Say you're running a 2. You'll have three 1. What you'll do is have three switches (relays).

One will switch on the first 1. The second will switch on both the first and second, giving you 2. The last will switch all three batteries into the circuit, giving you full power.

This is much less likely to kill you.. I won't draw up a diagram for you, but there are some out there to look up. I'll warn you that if you just draw one up, it's easy to wire things up such that you are dead- shorting a battery, which could weld your contacts cause the battery to explode if you are unable to break the circuit. Be careful. Be careful with this because your first battery to be switched on is going to drain much faster than your last battery. You will need to charge your batteries individually (not in series) and stop driving immediately when your performance with the first battery [/i]only[/i] starts to decline.

You will permanently damage your batteries if you over- discharge them. Lastly, you can use a controller.