Short answer: assuming the same cell chemistry and the same protection-board strategy, a 1050mAh does not age faster just because it holds more. What determines how quickly an LP-E17 ages is cell operating temperature, how deeply it is discharged each time, the charge level it sits at in storage, and whether charging current is excessive. Rated capacity is only a numerator. If anything, in the same body a 1050mAh is usually discharged less deeply per session, which favors cycle life. It is, however, more sensitive to heat and charging conditions, and mishandled it will fail sooner than a smaller pack.
Split “degradation” into two different things
When people say a battery “is done,” they are usually conflating two separate phenomena. The first is capacity loss: the pack now delivers only seventy or eighty percent of what it once did, so the same shooting load drains it faster. The second is rising internal resistance: capacity may still be eighty percent, but the moment you fit it and press the shutter the voltage sags, the body concludes the battery is low and shuts down, and when you take it out and put it back it shows two bars again.
The causes are not identical. Capacity loss tracks charge cycles, long storage at full charge, and high temperatures; rising resistance depends more on cell quality and sustained high-current discharge. A 1050mAh carries more cell material, so each cell usually discharges at a lower rate, which makes the resistance path less likely to be the first to give out.
So judging whether a high-capacity pack is aging fast takes more than frame counts; you also need to watch voltage stability in the low-charge region. This is why some packs show one bar and still deliver dozens of frames, while others shut down the moment they drop to one.
Why high-capacity packs get misread as aging faster
The first reason is longer charging. On the same LC-E17 dock, a 1050mAh typically takes ten or twenty minutes longer than a 950mAh. What the user perceives is not ten percent more capacity but “why isn’t this full yet,” and over time that leaves an impression that the pack is in poor shape.
The second is the shape of the discharge curve. High-capacity cells often hold a flatter voltage plateau through the first eighty percent, then fall steeply past the knee. Someone used to a 950mAh reads this as “solid for ages, then suddenly dead,” when in fact the total time is longer.
The third is how the gauge is read. Most bodies combine voltage estimation with a coulomb counter, and when you fit a pack of different capacity the body’s model does not change with it, so the first few readings may be conservative. Most bodies converge over three or four full cycles, though never exactly.
| What you observe | More likely cause | Is it degradation? |
|---|---|---|
| Charging takes longer than before | Larger capacity, or a fixed charger output | No |
| First two bars fall slowly, last bar falls fast | Position of the discharge-curve knee | No |
| Shows one bar and shuts down; a bar returns when refitted | Rising resistance, voltage sag under load | Yes |
| Twenty to thirty percent fewer frames for the same work | Capacity loss | Yes |
How to judge it yourself over a year
You do not need lab equipment. A fixed routine recorded three times is enough: when the pack is new, at about six months, and at one year. The key is keeping the shooting conditions as close as possible, otherwise the numbers are not comparable.
- Same body, same lens, same shooting mode, Wi-Fi and Bluetooth off, screen brightness at the same setting.
- Start from full and shoot single frames with minimal review until the body shuts itself off, then record the frame count. Do not review for long stretches mid-test; it skews the result significantly.
- Note the outdoor temperature. Below 10 degrees Celsius usable capacity drops by ten to twenty percent on its own, and skipping this note will distort the year-on-year comparison.
- Divide each frame count by the reference value for its temperature to get a relative capacity. Above eighty percent is normal, sixty to eighty is clearly aged but still usable as a backup, and below sixty means it should move to a secondary role.
If a full discharge test is impractical, there is a rougher method: shoot a normal day and compare the charge left in the evening with the same situation a year earlier. The error is larger, but the trend shows.
When 1050mAh actually lasts longer
One case is frequent bursts or long sessions with stabilization on. Those loads draw more current, and a larger pack runs at a shallower depth of discharge for the same frame count, putting less stress on the cell. The other is if you dislike running packs to shutdown: recharging with twenty or thirty percent left already reduces cycle wear, and a larger pack makes “still some left at the end of the day” easier to achieve.
Conversely, if you routinely charge to full and leave the pack in a bag for a month or two, or leave the camera in a car in summer, a 1050mAh will not age any better than a 950mAh. Hot storage at full charge is equally hard on both. The LP-E17 comes in 750, 950, and 1050mAh, and which tier suits you depends on your shooting rhythm rather than on which one is more durable. For the full picture on tiers and fitment, see the LP-E17 capacity and compatibility guide.
FAQ
Does 1050mAh have fewer cycles than the original?
Cycle count depends on the cell chemistry and the protection-board strategy, not the rated capacity. Canon’s original LP-E17 is about 1040mAh, the same order of magnitude as 1050mAh, and under normal use there will be no order-of-magnitude difference in cycle performance. Charging habits and storage temperature are what separate them.
After a year it drains faster. Did I waste my money?
Rule out the false alarms first: a different body, Wi-Fi left on, winter shooting, and heavier lens stabilization all make drain look faster. Run the fixed routine above once and compare with your first record. Only a real drop of more than twenty percent in relative capacity puts it in the aging range.
Should a high-capacity pack use a higher-current charger?
Not advisable. The LP-E17 charges in a dock and the current is set by the charger; ordinary users cannot adjust it. If you use a third-party portable charger, pick one rated close to the original. Excess current increases heat and shortens life. More on charging and cycles is in the 1050mAh category.
How should a spare be stored when not in use?
Charge it to about half, keep it in a dry box, away from light and at room temperature, and top it up every three or four months. Neither full nor empty storage is ideal: full accelerates aging of the positive electrode, and empty risks permanent damage from over-discharge.